Question 1

Which of the following best describes the first law of thermodynamics?

Accepted Answer

Energy cannot be created or destroyed, only transferred or transformed.

Question 2

A chemical reaction occurs in a sealed container at constant pressure. The system absorbs 150 J of heat and does 40 J of work on the surroundings. What is the change in internal energy $$\Delta U$$ for the system?

Accepted Answer

$$\Delta U = 110\ \mathrm{J}$$

Question 3

Which quantum number determines the shape of an atomic orbital?

Accepted Answer

Angular momentum quantum number $$l$$

Question 4

Which of the following electron configurations violates the Pauli Exclusion Principle?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$\ $$3p^7$$

Question 5

Which statement about Hund's Rule is correct?

Accepted Answer

Electrons occupy degenerate orbitals singly before pairing.

Question 6

Which of the following best explains why the atomic radius decreases across a period from left to right?

Accepted Answer

The nuclear charge increases, pulling electrons closer.

Question 7

Which element has the highest ionization energy among the following: Na, Mg, Al, Si?

Accepted Answer

Si

Question 8

A sample of gas undergoes a pressure-volume work of $$-75\ \mathrm{J} ($$work done on the system) and releases $$50\ \mathrm{J} of $$heat. What is the change in internal energy $$\Delta U$$?

Accepted Answer

$$\Delta U = 25\ \mathrm{J}$$

Question 9

Which of the following is the correct Lewis structure for carbon dioxide ($$\mathrm{CO_2$}$$)?

Accepted Answer

O=C=O, with each O atom having two lone pairs

Question 10

Which of the following statements about the Aufbau Principle is correct?

Accepted Answer

Electrons fill orbitals in order of increasing energy.

Question 11

Which of the following best describes the $$d$$ orbital shape?

Accepted Answer

Four-lobed or cloverleaf

Question 12

Which of the following is a correct statement about ionization energy?

Accepted Answer

It increases as you move across a period from left to right.

Question 13

Which of the following is the correct electron configuration for a neutral nitrogen atom?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^3$$

Question 14

Which of the following molecules contains a triple bond in its Lewis structure?

Accepted Answer

$$\mathrm{N_2$}$$

Question 15

A reaction has $$\Delta H = -200\ \mathrm{kJ}$$ and $$\Delta S = -50\ \mathrm{J/K}. At $$what temperature (in K) does the reaction become non-spontaneous? (Assume $$\Delta G = \Delta H - T\Delta S)$$

Accepted Answer

$$T \u003e 4000\ \mathrm{K}$$

Question 16

Which of the following best describes the process of writing a Lewis structure for $$\mathrm{H_2O}$$?

Accepted Answer

Place two single bonds between O and H, and assign two lone pairs to O.

Question 17

Which of the following statements about electron affinity is correct?

Accepted Answer

It generally increases across a period from left to right.

Question 18

Which of the following is the correct order of filling for the first 20 electrons in an atom according to the Aufbau Principle?

Accepted Answer

$$1s \rightarrow 2s \rightarrow 2p \rightarrow 3s \rightarrow 3p$$

Question 19

Which of the following best describes the spectrum of the hydrogen atom?

Accepted Answer

It consists of discrete lines corresponding to specific energy transitions.

Study Notes: Thermochemistry, Atomic Structure, Periodic Trends, and Chemical Bonding

Guida di studio - Domande di pratica

Study guide - Flashcard