Chemistry questions (CH205 TEST)

1.

Which of the following statements about heat is false?

[removed]A) If heat flows into a system, the extra energy of the system appears in the form of internal energy.
[removed]B) A hot object possesses more heat than a cold object.
[removed]C) If the system and surroundings are in thermal equilibrium, there is no heat flow between them.
[removed]D) A process in which heat flows out of a system is said to be exothermic.
[removed]E) Heat is a form of energy flow.

2.

Given:

60C(s) → C₆₀; ΔH = 2320 kJ

what is ΔH for the following thermochemical equation?

[removed]A) +38.7 kJ
[removed]B) +2320 kJ
[removed]C) -129 MJ
[removed]D) -2320 kJ
[removed]E) -38.7 kJ

3.

Exactly 173.9 J will raise the temperature of 10.0 g of a metal from 25.0°C to 60.0°C. What is the specific heat capacity of the metal?

[removed]A) 0.497 J/(g · °C)
[removed]B) 2.01 J/(g · °C)
[removed]C) 17.7 J/(g · °C)
[removed]D) 41.6 J/(g · °C)
[removed]E) none of these

4.

In a bomb calorimeter, reactions are carried out

[removed]A) at 1 atm pressure and 0°C.
[removed]B) at a constant pressure.
[removed]C) at a constant volume.
[removed]D) at a constant pressure and 25°C.
[removed]E) at 1 atm pressure and 25°C.

5.

The standard enthalpy change for which of the following processes corresponds to the standard enthalpy of formation of solid rubidium chloride?

[removed]A) Rb(s) + Cl₂(s) →RbCl(s)
[removed]B) Rb(g) + Cl₂(g) →RbCl(g)
[removed]C) Rb(g) + Cl(g) →RbCl(s)
[removed]D) Rb(s) + Cl₂(g) →RbCl(s)
[removed]E) Rb(s) + Cl₂(s) →RbCl(g)

6.

 What is the standard enthalpy of formation of liquid butyraldehyde, CH₃CH₂CH₂CHO(l)?

CH₃CH₂CH₂CHO(l) + O₂(g) → 4H₂O(l) + 4CO₂(g); ΔH°= -2471.8 kJ

[removed]A) –245.4 kJ/mol
[removed]B) +245.4 kJ/mol
[removed]C) –1792.5 kJ/mol
[removed]D) –3151.1 kJ/mol
[removed]E) +3151.1 kJ/mol

7.

Which of the following is not a fossil fuel?

[removed]A) anthracite coal
[removed]B) bituminous coal
[removed]C) natural gas
[removed]D) petroleum
[removed]E) glucose

8.

Rank the following regions of the electromagnetic spectrum in order of decreasing frequency.X rays, Microwaves, Infrared, Ultraviolet

[removed]A) infrared, microwaves, ultraviolet, x rays
[removed]B) x rays, microwaves, infrared, ultraviolet
[removed]C) microwaves, infrared, ultraviolet, x rays
[removed]D) microwaves, ultraviolet, infrared, x rays
[removed]E) x rays, ultraviolet, infrared, microwaves

9.

What is the frequency of a photon having an energy of 8.56 x 10^-16 J?

(c = 3.00 x 10⁸ m/s, h= 6.63 x 10^-34 J • s)

[removed]A) 3.88 x 10²⁶ Hz
[removed]B) 2.32 x 10^-10 Hz
[removed]C) 1.29 x 10¹⁸ Hz
[removed]D) 2.58 x 10^-27 Hz
[removed]E) 2.57 x 10^-7 Hz

10.

The number of orbitals having a given value of l is equal to

[removed]A) 2n + 1
[removed]B) 2l + 1
[removed]C) n + m_l
[removed]D) 2ml + 1
[removed]E) l + m_l

11.

How many orbitals have the set of quantum numbers n=3 and l=2?

[removed]A) 5
[removed]B) 9
[removed]C) 7
[removed]D) 1
[removed]E) 3

12.

Which of the following orbital occupancy designations is incorrect?

[removed]A) 2s¹
[removed]B) 2p⁶
[removed]C) 3d¹⁰
[removed]D) 4p⁷
[removed]E) 4f⁷

13.

The maximum number of electrons that can be accommodated in a d subshell is

[removed]A) 14
[removed]B) 6
[removed]C) 2
[removed]D) 1
[removed]E) 10

14.

Which principle or rule is violated by the following orbital diagram of an atom in its ground state?

[removed]A) Pauli exclusion principle
[removed]B) Aufbau principle
[removed]C) No rules or principles are violated by this orbital diagram.
[removed]D) Heisenberg uncertainty principle
[removed]E) Hund's rule

15.

Which of the following statements is incorrect?

[removed]A) A p-block main-group element belonging to period n has a completely filled (n – 1)d subshell.
[removed]B) All noble gases have completely filled shells.
[removed]C) All s-block main-group elements have only one or two valence electrons.
[removed]D) Carbon and silicon have the same number of valence electrons.
[removed]E) All elements in the n = 4 period have a partially or completely filled n = 4 shell.

16.

All of the following ground-state electron configurations are correct except

[removed]A)

Mn:[Ar]4s²4d⁵

[removed]B) K:[Ar]4s¹
[removed]C) Sn:[Kr]4d¹⁰5s²5p²
[removed]D) Cu:[Ar]3d¹⁰4s¹
[removed]E) I:[Kr]4d¹⁰5s²5p⁵

17.

Which of the following species would be expected to have chemical properties most similar to those of the nitrogen atom?

[removed]A) nitride ion
[removed]B) nitrite ion
[removed]C) phosphate ion
[removed]D) phosphide ion
[removed]E) phosphorus atom

18.

An atom of which of the following elements has the smallest atomic radius?

[removed]A) Cl
[removed]B) Rb
[removed]C) Mg
[removed]D) Ge
[removed]E) As

19.

Rank the following ions in order of increasing first ionization energy: O^2-, Mg²⁺, F^-, Na⁺.

[removed]A) Mg²⁺< Na⁺< F^-< O^2-
[removed]B) Mg²⁺< O^2-< Na⁺< F^-
[removed]C) O^2-< F^-< Mg²⁺< Na⁺
[removed]D) O^2-< F^-< Na⁺< Mg²⁺
[removed]E) O^2-< Mg²⁺< F^-< Na⁺

20.

Which element forms the most acidic oxide?

[removed]A) B
[removed]B) Tl
[removed]C) Al
[removed]D) In
[removed]E) Ga