General Chemistry Answers

7) Consider the species O^2-, F^-, Ne, Na⁺ and Mg²⁺. Which one of the following statements is INCORRECT?

A. O^2- has a larger radius than any of the other species.

B. Mg²⁺ is smaller than Ne.

C. More energy is required to remove an electron from Na⁺ than from Ne.

D. F^- has one electron more than Ne.

E. Na⁺ and Mg²⁺ are isoelectronic.

6) The energy of a photon (in J), that has a frequency of 18.21 x 10¹⁵ s^-1 is: 

A. 1.21 x 10^-17

B. 5.44 x10^-18

C. 1.99 x 10^-25

D. 3.49 x10^-48

E. 5.44 x10¹⁸

6) Which one of the following is NOT a valid set of four quantum numbers (n, ℓ, mℓ, ms)?

A. (2, 0, 0, +½)

B. (2, 1, 0,−½)

C. (3, 1, -1, −½)

D. (1, 0, 0, +½)

E. (1, 1, 0, +½)

How many filled p-orbitals are there in a Ne atom?

A. 0

B. 1

C. 6

D. 3

E. 2

Which principle or rule is violated by the following orbital-filling diagram of an

 atom in its ground state?

1s 2s 2p

↑↓ ↑↓ ↑↓ ↑

A. Pauli’s exclusion principle

B. Hund's rule

C. The Aufbau principle

D. Heisenberg’s uncertainty principle

E. No rules or principles are violated by this orbital diagram

What is the energy in joules of one mole of photons associated with red light of

wavelength 7.00 x 10² nm?

A. 1.71 x 105

J B. 12.4 kJ

C. 4.72 x 10^-43 J

D. 256 kJ

E. 2.12 x 10⁴² J

6) The first four ionization energies of atoms of elements X, Y and Z are given below (where M = X, Y,Z):

IONISATION ENERGY

ELEMENT M FIRST SECOND THIRD FOURTH

X 738 1450 7730 10550

Y 800 2427 3658 25024

Z 495 4563 6912 9540

Which element/s M is/are most likely to have a nitride compound with formula MN?

A. X

B. Y

C. Z

D. Both X and Y

E. Both Y and Z

6) If the wavelength of an electromagnetic wave is halved, the energy of the photon associated with it would:

A. halve

B. decrease by 50%

C. double

D. increase by 50%

E. Remain the same

6) Which atom in its ground-state has an electron configuration described by the following orbital diagram?

[Ar] ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↑

4s 3d 4p

A. Phosphorus

B. Germanium

C. Selenium

D. Tellurium

E. None of these

6) How many electrons in an atom can have the following set of quantum numbers?

 n = 4                   ℓ = 3            mℓ = −2                   ms = +1/2

A. 0

B. 1

C. 2

D. 6

E. 10