Joint Entrance Examination main (JEE main)

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Jee Main Test Subjects: Math, Physics & Chemistry 90 Questions 60 MCQs 30 Numeric Value Questions 300 Marks Time 180 Minute Prep with other candidates

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Joint Entrance Examination main (JEE main)

All About JEE Main Exam


Fani Warraich PHYSICS   -   Electromagnetism

The Net Magnetic flux from any closed surface is

This is because the net magnetic flux through any closed surface is always zero. This is known as Gauss's law for magnetism. It is a consequence of the fact that there are no magnetic monopoles, meaning that magnetic field lines always form closed loops.
Fani Warraich MATHEMATICS   -   Algebra

Solve the equation 2/6 (3a + 2b) – 1/2 (2a + 4b) -2(12a – 6b)?

Fani Warraich MATHEMATICS   -   Calculus

The solution set of the inequality |x + 4| ≥ 2 is

Fani Warraich MATHEMATICS   -   Discrete Mathematics

If p= It is raining q = She will go to college. "It is raining and she will not go to college” will be denoted by

Bashir Farooqi MATHEMATICS   -   Discrete Mathematics

The negation of “Today is Friday” is

Bashir Farooqi MATHEMATICS   -   Discrete Mathematics

Contra-positive of given statement “If it is raining, I will take an umbrella” is

Bashir Farooqi MATHEMATICS   -   Discrete Mathematics

A statement is also referred to as a

Bashir Farooqi MATHEMATICS   -   Discrete Mathematics

The statement ~ (~ ) p = p Describes

Bashir Farooqi MATHEMATICS   -   Discrete Mathematics

An arrangement of rows and columns that specifies the truth value of a compound proposition for all possible truth values of its constituent propositions is called

Bashir Farooqi MATHEMATICS   -   Discrete Mathematics

An argument is _____ if the conclusion is true when all the premises are true.

Bashir Farooqi MATHEMATICS   -   Discrete Mathematics

The row in the truth table of an argument where all premises are true is called

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The number of degrees through which the hour hand of a clock moves in 2 hours and 12 minutes is

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A cylindrical container has a diameter of 14 inches and a height of 6 inches. Since one gallon equals 231 cubic inches, the capacity of the tank is approximately

The capacity of the tank is given by πr^2h = π(7^2)(6) = 923.628 cubic inches Since 1 gallon is equal to 231 cubic inches, the capacity of the tank in gallons is 923.628 / 231 = 3.998 gallons Which is approximately 4 gallons. So the answer is B.
Fani Warraich

4 gallons is the correct

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A train running between two towns arrives at its destination 10 minutes late when it goes 40 miles per hour and 16 minutes late when it goes 30 miles per hour. The distance between the two towns is

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If the base of a rectangle is increased by 30% and the altitude is decreased by 20% the area is increased by?

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If the sum of the edges of a cube is 48 inches, the volume of the cube is

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A certain triangle has sides, which are, respectively, 6 inches, 8 inches, and 10 inches long. A rectangle equal in area to that of the triangle has a width of 3 inches. The Perimeter of the rectangle, expressed in inches, is

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The cube of 1/3 is

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

In general, the sum of the squares of two numbers is greater than twice the product of the numbers. The pair of numbers for which this generalization is not valid is

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A piece of wire 132 inches long is bent successively in the shape of an equilateral triangle, a square, a regular hexagon, a circle. The plane surface of the largest area is included when the wire is bent into the shape of a

Bashir Farooqi IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If eggs are bought at 35 cents per dozen and sold at 3 for 10 cents the total profit on 5 1/2 dozen is?

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A piece of wood 35 feet, 6 inches long was used to make 4 shelves of equal length. The length of each shelf was

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The tiles in the floor of a kitchen are 15/16 inch squares. The cement between the tiles is 1/16 inch. There are 3240 individual tiles in this floor. The area of the floor is

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A man bought a TV set that was listed at Rs.160. He was given successive discounts of 20% and 10%. The price he paid was

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Mr. Younas ' income for a year is Rs.15,000. He pays 15% of this in federal taxes and 10% of the remainder in state taxes. How much is left?

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The radius of a circle which has a circumference equal to the perimeter of a hexagon whose sides are each 22 inches long is closest in length to which one of the following?

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If a, is a multiple of 5 and b = 5a, which of the following could be the value of a + b? I. 60 II. 100 III. 150

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Which of the following expressions has the greatest value?

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If (a + 3) / 5 is an integer, what is remainder when ‘a’ is divided by 5?

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The integral part of logarithm is called

Muhammad Tayyab Ikhlas IQ APTITUDE & ABILITY   -   Quantitative Reasoning

On the y-axis, the x-coordinate is

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

How many bricks each measuring 25cm x 11.25cm x 6cm, will be needed to build a wall of size 8m x 6m x 22.5m ?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The profit earned by selling an article for Rs. 900 is double the loss incurred when the same article is sold for Rs. 490. At what price should the article be sold to make 25% profit?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

An air conditioner can cool the hall in 40 minutes while another takes 45 minutes to cool under similar conditions. If both air conditioners are switched on at the same instance, then how long will it approximately take to cool the room?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A person crosses a 600 m long street in 5 minutes. What is his speed in km per hour?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

What should come in place of both the question marks in the equation: ? / √128 = √162 / ?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

In an examination, a student scores 4 marks for every correct answer and loses 1 mark for every wrong answer. If he attempts all 60 questions and secures 130 marks, the no of questions he attempts correctly is :

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Kajol took loan from a bank at the rate of 12% p.a. simple interest. After 3 years, she had to pay PKR 5400 interest only for the period. The principal amount borrowed by her was:

We can use the following formula to calculate the simple interest: Simple Interest = (Principal * Rate * Time) / 100 Where: Principal is the amount of money borrowed. Rate is the interest rate per year. Time is the number of years the loan is borrowed for. We know that the simple interest is PKR 5400, the rate is 12% p.a., and the time is 3 years. We need to calculate the principal. Substituting the known values into the formula, we get: 5400 = (Principal * 12 * 3) / 100 Multiplying both sides of the equation by 100, we get: 540000 = Principal * 12 * 3 Dividing both sides of the equation by 12 * 3, we get: Principal = 540000 / (12 * 3) Principal = PKR 15000 Therefore, the principal amount borrowed by Kajol was PKR 15000.
Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Salaries of Conan and Jimmy are in the ratio 2:3. If the salary of each is increased by Rs. 4000, the new ratio becomes 40:57. What is Jimmy’s salary?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A person incurs a loss of 5% be selling a watch for Rs. 1140. At what price should the watch be sold to earn 5% profit?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Two trains started at the same time, one from A to B and the other from B to A . If they arrived at B and A respectively 4 hours and 9 hours after they passed each other, the ratio of the speeds of the two trains was:

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The sum of the squares of two numbers is 3341 and the difference of their squares is 891. The numbers are:

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The average age of a class is 15.8 years. The average age of the boys in the class is 16.4 years and that of the girls is 15.4 years. What is the ratio of boys to girls in the class ?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

In a class, there are 15 boys and 10 girls. Three students are selected at random. The probability that 1 girl and 2 boys are selected, is:

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A water tank in a village is normally filled in 8 hours but takes 2 hours longer to fill because of a leak in its bottom. If the tank is full, in how many hrs will the leak empty it ?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A college has 10 basketball players. A 5-member team and a captain will be selected out of these 10 players. How many different selections can be made?

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If the price of a Harry Potter novel is first decreased by 25% and then increased by 20%, then the net change in the price will be :

Suzico IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Shruti and Priya invested in a business. They earned some profit which they divided in the ratio of 2 : 3. If Shruti invested Rs. 40,000, the amount invested by Priya is :

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Each of Tom's buckets has a capacity of 11 gallons, while each of Henry's buckets can hold 8 gallons. How much more water in gallons can 7 of Tom's bucket's hold compared to 7 of Henry's buckets?

Fani Warraich

Good

Fani Warraich

A

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Two integers have a sum of 42 and a difference of 22. The greater of the two integers is

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The average of five numbers is 34. If three of the numbers are 28, 30 and 32, what is the average of the other two?

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

In a certain cake, two straight cuts (made along two different radii) succeed in removing 4/15 of the total cake. What is the central angle in degrees of the piece cut?

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If an equilateral triangle and a square have the same perimeter, what is the ratio of the length of the sides of the equilateral triangle to the lengths of the sides of the square?

Let the side length of the equilateral triangle be x and the side length of the square be y. Since they have the same perimeter, we know that: 3x=4y Dividing both sides by 3, we get: x= 4/3(y) Therefore, the ratio of the side lengths of the equilateral triangle to the side lengths of the square is 4:3.
Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If 2 and 4 each divide q without remainder, which of the following must q divide without remainder.

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The ratio of boys to girls in a certain classroom was 2 : 3. If boys represented five more than one third of the class, how many people were there in the classroom?

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Let xy = z, where x,y,z and nonzero numbers. If x is multiplied by 3 and z is divided by 3, this is equivalent to multiplying y by

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If 5x = 3, then (5x + 3)² =

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If the postal charges for a package are 62 cents for the first five ounces and 8 cents for each additional ounce, what is the weight of a package for which the charges are $1.66? (Assume there are 16 ounces in one pound)

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If m/n = .75, then what is 3m + 2n?

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Which is greater? Column A is (10/4) / (3/2) * (3/7) and Column B is (3/4) * (10/7) / (3/2)

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Which of the following has a graph that is symmetric to the x-axis

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The prime factors of 96 are

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

2- 3 =

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If x + 1 < 3x + 5, then

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

Which of the numbers cannot be represented by a repeating decimal?

Fani Warraich IQ APTITUDE & ABILITY   -   Quantitative Reasoning

A train moves at sixty miles per hour from City A to City B and eighty miles per hour from City B to City A in reverse. What is the distance between the two cities if the round-trip travel duration is eight hours?

Peacel awfirm IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If half the range of increasing series {11, A, 23, B, C, 68, 73} is equal to its median, what is the median of the series?

Let's analyze the given series: {11, A, 23, B, C, 68, 73}. The median of a series is the middle value when the values are arranged in ascending order. In this case, the series is already in increasing order: {11, A, 23, B, C, 68, 73} Now, if half the range is equal to the median, we need to find the range and divide it by 2. Range = Largest value - Smallest value In this series, the largest value is 73, and the smallest value is 11. Range = 73 - 11 = 62 Half the range = 62 / 2 = 31 Now, we need to find the element in the series that is 31 units away from the smallest value (11). Counting 31 units from 11, we get: 11 + 31 = 42 So, the element with the value 42 is the median of the series. Therefore, the median of the series {11, A, 23, B, C, 68, 73} is 42.
Peacel awfirm IQ APTITUDE & ABILITY   -   Quantitative Reasoning

The product of (1+2), (2+3) and (3+4) is equal to the one-half the sum of 20 and x, what is the value of x?

Peacel awfirm IQ APTITUDE & ABILITY   -   Quantitative Reasoning

What k is subtracted from10 and difference is divided by 2, the result is 3, what is the value of k?

Peacel awfirm IQ APTITUDE & ABILITY   -   Quantitative Reasoning

If a^2 b =12^2, and b is smallest odd integer, then a could be divisible by all of the following except?

Peacel awfirm IQ APTITUDE & ABILITY   -   Quantitative Reasoning

900/10 + 90/100 + 9/1000 = ?

Gitofa Shah PHYSICS   -   Statistical Mechanics

What is the name of the statistical ensemble that describes a system with a fixed number of particles, volume, and energy?

The microcanonical ensemble describes a closed system with a fixed number of particles (N), volume (V), and energy (E), and is characterized by a fixed energy and particle number.
Gitofa Shah PHYSICS   -   Statistical Mechanics

A system is in thermal equilibrium with a reservoir at temperature T. What is the probability of finding the system in a microstate with energy E?

The probability of finding a system in a microstate with energy E is given by the Boltzmann distribution, which is proportional to e^(−E/kT) and normalized by the partition function Z(T).
Gitofa Shah PHYSICS   -   Statistical Mechanics

What is the name of the theorem that relates the entropy of a system to the number of possible microstates?

Boltzmann's theorem states that the entropy of a system is proportional to the logarithm of the number of possible microstates, S = k * ln(Ω).
Gitofa Shah PHYSICS   -   Statistical Mechanics

A system undergoes a reversible adiabatic process. What is the change in entropy of the system?

In a reversible adiabatic process, the entropy of the system remains constant, ΔS = 0.
Gitofa Shah PHYSICS   -   Statistical Mechanics

What is the name of the statistical mechanical potential that describes a system at constant temperature and pressure?

The Gibbs free energy is a statistical mechanical potential that describes a system at constant temperature and pressure, and is defined as G = H - TS, where H is the enthalpy and S is the entropy.
Gitofa Shah PHYSICS   -   Electromagnetism

A charged particle moves with a velocity v = 0.6c in a region with a uniform magnetic field B = 2T. What is the magnitude of the force experienced by the particle if its charge is q = 3 × 10^(-6) C?

The force experienced by a charged particle in a magnetic field is given by F = qvB sin(θ), where θ is the angle between the velocity and magnetic field vectors. In this case, since the velocity and magnetic field are perpendicular, sin(θ) = 1, and F = qvB = 3 × 10^(-6) C × 0.6 × 3 × 10^8 m/s × 2 T = 3.6 × 10^(-2) N.
Gitofa Shah PHYSICS   -   Electromagnetism

A parallel-plate capacitor has a capacitance C = 5 μF and is charged to a voltage V = 12 V. If the plates are separated by a distance d = 2 mm, what is the energy density of the electric field between the plates?

The energy density of the electric field between the plates is given by u = (1/2)ε₀E^2, where ε₀ is the permittivity of free space and E is the electric field strength. The electric field strength is given by E = V/d = 12 V / 2 × 10^(-3) m = 6 × 10^3 V/m. Substituting this value, we get u = (1/2) × 8.85 × 10^(-12) C^2/Nm^2 × (6 × 10^3 V/m)^2 = 1.8 × 10^5 J/m^3.
Gitofa Shah PHYSICS   -   Electromagnetism

A coil of 500 turns and cross-sectional area A = 0.02 m^2 is placed in a region with a uniform magnetic field B = 0.1 T. If the coil is rotated at a constant angular velocity ω = 20 rad/s, what is the maximum emf induced in the coil?

The maximum emf induced in the coil is given by ε = N × (dΦ/dt), where N is the number of turns, Φ is the magnetic flux, and d/dt is the derivative with respect to time. The magnetic flux is given by Φ = B × A × cos(ωt), where ω is the angular velocity and t is time. Substituting the values, we get ε = 500 × (0.1 T × 0.02 m^2 × cos(20 rad/s × t))/dt = 6.28 V.
Gitofa Shah PHYSICS   -   Electromagnetism

A beam of light with a wavelength λ = 500 nm is incident on a diffraction grating with 5000 lines per meter. What is the angular separation between the first-order maxima?

The angular separation between the first-order maxima is given by Δθ = λ/d, where d is the grating spacing. The grating spacing is given by d = 1/5000 m = 2 × 10^(-4) m. Substituting the values, we get Δθ = 500 × 10^(-9) m / 2 × 10^(-4) m = 0.1 rad
Gitofa Shah PHYSICS   -   Thermodynamics

A heat engine operates between two reservoirs at temperatures T1 and T2, with T1 > T2. What is the maximum efficiency of the engine?

The maximum efficiency of a heat engine is given by the Carnot efficiency, which is 1 - (T2 / T1), where T1 is the temperature of the hot reservoir and T2 is the temperature of the cold reservoir.
Gitofa Shah PHYSICS   -   Thermodynamics

A system undergoes a reversible isothermal expansion from volume V1 to V2. What is the change in internal energy of the system?

In a reversible isothermal process, the temperature remains constant, and the change in internal energy is zero, ΔU = 0.
Gitofa Shah PHYSICS   -   Thermodynamics

What is the name of the process by which a system transitions from a metastable state to a stable state with a decrease in free energy?

Nucleation is the process by which a system transitions from a metastable state to a stable state with a decrease in free energy, often accompanied by the formation of a new phase.
Gitofa Shah PHYSICS   -   Thermodynamics

A gas is compressed adiabatically from pressure P1 to P2. What is the change in temperature of the gas?

In an adiabatic compression, the temperature of the gas increases according to the relation T2 = T1 * (P2 / P1)^(γ - 1), where γ is the adiabatic index.
Gitofa Shah PHYSICS   -   Thermodynamics

What is the name of the thermodynamic potential that describes a system at constant pressure and temperature?

The Gibbs free energy is a thermodynamic potential that describes a system at constant pressure and temperature, and is defined as G = H - TS, where H is the enthalpy and S is the entropy.
lorrin mike PHYSICS   -   Biophysics

What is the primary reason for the asymmetry of the protein structure?

Hydrophobic interactions play a crucial role in protein folding, leading to an asymmetric distribution of hydrophobic and hydrophilic residues.
lorrin mike PHYSICS   -   Biophysics

Which technique would you use to study the dynamics of a protein-ligand interaction?

Molecular dynamics simulations can provide detailed information on the dynamics of protein-ligand interactions, including binding and unbinding processes.
lorrin mike PHYSICS   -   Biophysics

What is the name of the process by which cells generate force to move or change shape?

Cytoskeleton dynamics involve the generation of force through the interaction of cytoskeletal elements, such as actin and myosin.
lorrin mike PHYSICS   -   Biophysics

Which biophysical technique measures the rotation of a molecule around its axis?

Fluorescence anisotropy measures the rotation of a molecule around its axis, providing information on its dynamics.
lorrin mike PHYSICS   -   Biophysics

What is the term for the minimum energy required for a protein to fold into its native structure?

Activation energy is the minimum energy required for a protein to overcome the energy barrier and fold into its native structure.
lorrin mike PHYSICS   -   Biophysics

Which type of spectroscopy measures the vibrational modes of molecules?

Infrared spectroscopy measures the vibrational modes of molecules, providing information on their structure and dynamics.
lorrin mike PHYSICS   -   Biophysics

What is the name of the process by which cells sense and respond to mechanical forces?

Mechanotransduction is the process by which cells sense and respond to mechanical forces, converting them into biochemical signals.
lorrin mike PHYSICS   -   Biophysics

Which biophysical technique measures the distance between two points in a biomolecule?

FRET measures the distance between two points in a biomolecule, typically in the range of 1-10 nm.
lorrin mike PHYSICS   -   Biophysics

What is the term for the study of the physical principles underlying biological systems?

Biophysics is the study of the physical principles underlying biological systems, aiming to understand the behavior of biological systems in terms of physical laws and principles.
lorrin mike PHYSICS   -   Biophysics

Which type of microscopy uses a focused laser beam to image biological samples?

Confocal microscopy uses a focused laser beam to image biological samples, providing high-resolution images with reduced background fluorescence.
lorrin mike PHYSICS   -   Atomic Physics

Which quantum number specifies the shape of an atomic orbital?

The orbital quantum number (l) determines the shape of an atomic orbital. It ranges from 0 to (n-1), where n is the principal quantum number.
lorrin mike PHYSICS   -   Atomic Physics

Which phenomenon occurs when an electron moves from a higher to a lower energy level within an atom, emitting a photon?

Emission occurs when an electron transitions from a higher energy level to a lower one within an atom, releasing energy in the form of a photon.
lorrin mike PHYSICS   -   Atomic Physics

Which element has the electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶?

The electron configuration given belongs to Xenon (Xe), a noble gas with atomic number 54.
lorrin mike PHYSICS   -   Atomic Physics

Which of the following transitions in the hydrogen atom results in the emission of the highest energy photon?

The energy of emitted photons in hydrogen atom transitions is highest when the electron falls from a higher energy level to a lower one. The transition from n = 4 to n = 5 corresponds to the highest energy difference among the options provided.
lorrin mike PHYSICS   -   Atomic Physics

What is the term for the minimum amount of energy required to remove an electron from the outermost shell of an atom in its ground state?

Ionization energy is the energy required to completely remove an electron from an atom or ion in its ground state. It is a measure of the atom's ability to hold onto its electrons.
lorrin mike PHYSICS   -   Nuclear Physics

Which of the following particles is emitted during beta-minus decay?

Beta-minus decay involves the emission of an electron (beta particle) from a nucleus. This occurs when a neutron in the nucleus converts into a proton, releasing an electron and an antineutrino.
lorrin mike PHYSICS   -   Nuclear Physics

Which nuclear reaction is responsible for the energy production in the Sun and other stars?

Nuclear fusion is the process where light atomic nuclei combine to form heavier nuclei, releasing a significant amount of energy. It is the primary energy source for stars, including the Sun.
lorrin mike PHYSICS   -   Nuclear Physics

What is the fundamental force responsible for binding protons and neutrons together in the nucleus?

The strong nuclear force is the fundamental force that binds protons and neutrons (nucleons) together in the nucleus. It is a short-range force that overcomes the repulsive electromagnetic force between protons.
lorrin mike PHYSICS   -   Nuclear Physics

Which of the following particles has the same charge as an electron but approximately 1836 times greater mass?

A proton has the same charge as an electron (positive) but is much heavier, with a mass approximately 1836 times greater than that of an electron.
lorrin mike PHYSICS   -   Nuclear Physics

What is the approximate binding energy per nucleon in a typical stable nucleus?

The binding energy per nucleon represents the average energy required to completely separate a nucleus into its individual nucleons. It is approximately 8 MeV for stable nuclei, indicating the stability and compactness of nuclear structure.
lorrin mike PHYSICS   -   Astrophysics

Which of the following types of electromagnetic radiation has the shortest wavelength?

Gamma rays have the shortest wavelength among the options listed. They are high-energy photons with wavelengths shorter than X-rays.
lorrin mike PHYSICS   -   Astrophysics

What is the approximate surface temperature of the Sun?

The surface temperature of the Sun is approximately 5,500 degrees Kelvin (K).
lorrin mike PHYSICS   -   Astrophysics

What phenomenon causes the shift in spectral lines towards longer wavelengths in astrophysical objects moving away from Earth?

The Doppler effect causes the shift in spectral lines towards longer wavelengths (redshift) for objects moving away from Earth and towards shorter wavelengths (blueshift) for objects moving towards Earth.
lorrin mike PHYSICS   -   Astrophysics

Which of the following is a remnant of a massive star that has undergone a supernova explosion?

A neutron star is the compact remnant left behind after a massive star explodes in a supernova.
lorrin mike PHYSICS   -   Astrophysics

What is the name of the boundary surrounding a black hole beyond which nothing, not even light, can escape?

The event horizon is the boundary surrounding a black hole from within which nothing can escape its gravitational pull, not even light.
lorrin mike PHYSICS   -   Astrophysics

Which type of galaxy is characterized by a flat disk containing young stars, gas, and dust, with spiral arms extending outward from a central bulge?

Spiral galaxies have a distinct flattened disk structure with spiral arms emanating from a central bulge, containing young stars, gas, and dust.
lorrin mike PHYSICS   -   Astrophysics

What is the primary source of energy generation in main-sequence stars like the Sun?

Main-sequence stars like the Sun generate energy through nuclear fusion, specifically the fusion of hydrogen into helium in their cores.
lorrin mike PHYSICS   -   Astrophysics

What theoretical concept describes the gravitational collapse of a massive star into an infinitely dense point, resulting in a gravitational singularity?

A black hole is a region of spacetime where gravity is so intense that not even light can escape from it, formed by the collapse of a massive star.
lorrin mike PHYSICS   -   Astrophysics

Which phenomenon describes the bending of light around a massive object due to gravity?

Gravitational lensing occurs when light from a distant object is bent as it passes near a massive object, like a galaxy or a black hole, due to the gravitational field of the massive object.
lorrin mike PHYSICS   -   Astrophysics

What is the predominant element found in the universe by mass fraction?

Hydrogen is the most abundant element in the universe by mass fraction, constituting about 75% of the mass of all normal matter.
Malen Bara CHEMISTRY   -   Organic Chemistry

Which of the following statements about the bonding in ethyne (acetylene, C2H2) is correct?

In ethyne, each carbon atom is sp hybridized, forming a linear molecule with a bond angle of 180 degrees. The carbon atoms are connected by a triple bond consisting of one sigma bond and two pi bonds.
Malen Bara CHEMISTRY   -   Organic Chemistry

Which of the following functional groups can act as both an acid and a base?

Amines contain a nitrogen atom with a lone pair of electrons, which allows them to act as a base by accepting a proton. They can also act as weak acids by donating a proton from the hydrogen atoms attached to the nitrogen, although this is less common compared to their basicity.
Malen Bara CHEMISTRY   -   Organic Chemistry

Which of the following compounds is chiral?

2-Butanol has a carbon atom (the second carbon) attached to four different groups: a hydroxyl group (-OH), a methyl group (-CH3), an ethyl group (-CH2CH3), and a hydrogen atom. This makes it chiral, possessing non-superimposable mirror images (enantiomers).
Malen Bara CHEMISTRY   -   Organic Chemistry

In which of the following reactions does the formation of a carbocation intermediate occur?

The SN1 reaction mechanism involves two steps. The first step is the dissociation of the leaving group, leading to the formation of a carbocation intermediate. This carbocation then reacts with a nucleophile in the second step.
Malen Bara CHEMISTRY   -   Organic Chemistry

What is the first step in the retrosynthetic analysis of 1-bromo-2-phenylethane?

Retrosynthetic analysis involves breaking down the target molecule into simpler precursor structures. For 1-bromo-2-phenylethane, identifying how the phenyl group is attached to the ethane chain is crucial for determining the precursor molecules. In this case, one might consider the synthesis from ethylbenzene or from styrene via bromination.
Malen Bara CHEMISTRY   -   Organic Chemistry

In proton NMR spectroscopy, what splitting pattern would you expect for the protons on the methylene group in ethyl acetate (CH3COOCH2CH3)?

The methylene group (CH2) in ethyl acetate is adjacent to a methyl group (CH3), which causes spin-spin coupling. The three protons of the methyl group split the signal of the two methylene protons into a quartet due to the n+1 rule (n=3).
Malen Bara CHEMISTRY   -   Organic Chemistry

Which of the following compounds is not aromatic?

Benzene, pyridine, and naphthalene all obey Huckel's rule for aromaticity, possessing (4n+2) π-electrons and a planar structure. Cyclooctatetraene, however, does not adopt a planar conformation and does not have (4n+2) π-electrons, making it non-aromatic.
Malen Bara CHEMISTRY   -   Organic Chemistry

In an electrophilic aromatic substitution reaction, which intermediate is formed?

In electrophilic aromatic substitution, the intermediate formed is a sigma complex (also known as an arenium ion or Wheland intermediate). This intermediate features a partially positive charge and a disrupted aromatic system, which is later restored upon deprotonation.
Malen Bara CHEMISTRY   -   Organic Chemistry

Which of the following statements about the polymerization of ethylene to form polyethylene is correct?

The polymerization of ethylene to form polyethylene is typically carried out via a free radical mechanism. This process involves the initiation, propagation, and termination steps, where free radicals mediate the addition of ethylene monomers to the growing polymer chain.
Malen Bara CHEMISTRY   -   Organic Chemistry

Which of the following heterocycles contains nitrogen and is aromatic?

Pyrrole is a five-membered heterocyclic compound containing nitrogen and is aromatic. It has a planar structure with a conjugated system of (4n+2) π-electrons, making it aromatic according to Huckel's rule.
Malen Bara CHEMISTRY   -   Organic Chemistry

Which type of enzyme catalysis involves the formation of a covalent bond between the enzyme and the substrate?

In covalent catalysis, a transient covalent bond is formed between the enzyme and the substrate during the reaction. This temporary covalent intermediate helps stabilize the transition state and lower the activation energy of the reaction.
Malen Bara CHEMISTRY   -   Organic Chemistry

Which of the following principles is not one of the Twelve Principles of Green Chemistry?

Increasing chemical yields is not explicitly one of the Twelve Principles of Green Chemistry. While yield is important, the principles focus on reducing waste, minimizing the use of hazardous substances, and designing environmentally benign processes.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following elements has the highest second ionization energy?

The second ionization energy is the energy required to remove the second electron after the first has been removed. Sodium has a very high second ionization energy because removing the second electron means disrupting a stable noble gas configuration (Ne), making it significantly more difficult than the first ionization.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following molecules has the most polar bond?

Polarity of a bond is determined by the difference in electronegativity between the two bonded atoms. Fluorine is the most electronegative element, and the electronegativity difference between hydrogen and fluorine is the greatest among the given pairs, making HF the most polar bond.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

In a face-centered cubic (fcc) lattice, what is the coordination number of each atom?

In a face-centered cubic (fcc) lattice, each atom is surrounded by 12 nearest neighbors. This coordination number of 12 arises because each atom touches four atoms in its own layer, four atoms in the layer above, and four atoms in the layer below.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following ligands will cause the greatest splitting in the d-orbital energies of a central metal ion according to the spectrochemical series?

According to the spectrochemical series, CN⁻ is a strong field ligand and causes significant splitting of the d-orbitals in a central metal ion. This large splitting can lead to different electronic configurations and affects the color and magnetic properties of the complex.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

In the compound ferrocene (Fe(C5H5)2), what is the oxidation state of the iron center?

In ferrocene, each cyclopentadienyl anion (C5H5⁻) is considered to donate 6 electrons to the iron atom, providing a total of 12 electrons. Iron in the neutral state (Fe) has 8 valence electrons, leading to the 18-electron configuration that stabilizes the complex. Hence, the oxidation state of iron in ferrocene is 0.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which metal ion is at the active site of the enzyme carbonic anhydrase?

Carbonic anhydrase is an enzyme that catalyzes the hydration of carbon dioxide. The active site of this enzyme contains a zinc ion (Zn²⁺) which is coordinated by three histidine residues and a water molecule, playing a crucial role in the enzyme's catalytic function.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following elements forms a stable diatomic molecule in the gas phase?

Nitrogen forms a stable diatomic molecule (N₂) due to the formation of a strong triple bond between the two nitrogen atoms, making it very stable. The other elements listed typically form more complex molecular structures or allotropes.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following transition metals exhibits the highest number of oxidation states?

Manganese exhibits the highest number of oxidation states, ranging from -3 to +7. This wide range of oxidation states is due to its electronic configuration, which allows it to lose or share various numbers of electrons.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following actinides is commonly used as a fuel in nuclear reactors?

Uranium, specifically U-235, is commonly used as a fuel in nuclear reactors due to its ability to undergo fission and release a significant amount of energy. Thorium can also be used in nuclear reactors, but it is less common compared to uranium.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following compounds acts as both a Lewis acid and a Lewis base?

Water (H₂O) can act as both a Lewis acid (accepting a pair of electrons when it forms H₃O⁺) and a Lewis base (donating a pair of electrons when it acts as a solvent or forms coordinate bonds). The other compounds typically act only as Lewis acids or bases.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following is a typical example of an inner-sphere electron transfer reaction?

An inner-sphere electron transfer involves a bridging ligand that temporarily connects the two reactants. In the reduction of MnO₄⁻ by Fe²⁺, an intermediate complex can form where a ligand bridges the Mn and Fe centers, facilitating the electron transfer.
Malen Bara CHEMISTRY   -   Inorganic Chemistry

Which of the following methods is commonly used to synthesize graphene?

Chemical vapor deposition (CVD) is a common method used to synthesize high-quality graphene. This process involves the deposition of carbon atoms onto a substrate from a gas-phase precursor, resulting in the formation of a graphene layer.

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