Question 1

Which of the following statements best describes the law of definite proportions?

Accepted Answer

A compound always contains exactly the same proportion of elements by mass.

Question 2

A sample of a compound contains 4.00 g of hydrogen and 32.00 g of oxygen. What is the empirical formula of the compound?

Accepted Answer

$$\mathrm{H_2O}$$

Question 3

Which of the following is a chemical property?

Accepted Answer

Iron rusts in moist air.

Question 4

Which of the following is the correct electron configuration for a ground-state phosphorus atom ($$Z=15$$)?

Accepted Answer

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

Question 5

Which of the following best explains why the boiling point of water is higher than that of hydrogen sulfide ($$\mathrm{H_2S}$$)?

Accepted Answer

Water forms hydrogen bonds, which are stronger than the dipole-dipole interactions in $$\mathrm{H_2S}.$$

Question 6

A 5.00 g sample of an unknown metal at $$100\ ^\circ\mathrm{C} is $$placed in 100.0 g of water at $$25.0\ ^\circ\mathrm{C}. $$The final temperature is $$26.0\ ^\circ\mathrm{C}. $$What is the specific heat capacity of the metal? ($$c_{\mathrm{water}} = 4.18\ \mathrm{J/g\cdot ^\circ C})$$

Accepted Answer

$$0.08\ \mathrm{J/g\cdot ^\circ C}$$

Question 7

Which of the following molecules has the largest dipole moment?

Accepted Answer

$$\mathrm{HF}$$

Question 8

Which of the following is the correct net ionic equation for the reaction between aqueous solutions of $$\mathrm{$$AgNO_3$$}$$ and $$\mathrm{NaCl}$$?

Accepted Answer

$$\mathrm{Ag^+ (aq) + Cl^- (aq) \rightarrow AgCl (s)}$$

Question 9

Which of the following statements about the periodic table is correct?

Accepted Answer

Elements in the same group have similar chemical properties.

Question 10

Which of the following is the correct balanced equation for the combustion of propane ($$\mathrm{C_3H_8}$$)?

Accepted Answer

$$\mathrm{C_3H_8 + 5O_2 \rightarrow 3CO_2 + 4H_2O}$$

Question 11

Which of the following best describes the shape of a $$\mathrm{CH_4$}$$ molecule according to VSEPR theory?

Accepted Answer

Tetrahedral

Question 12

Which of the following is the correct formula for aluminum sulfate?

Accepted Answer

$$\mathrm{Al_2$(SO_4$)_3}$$

Question 13

A gas sample occupies $$2.50\ \mathrm{L} at$$ $$1.00\ \mathrm{atm}$$ and $$25.0\ ^\circ\mathrm{C}. $$What volume will it occupy at $$2.00\ \mathrm{atm}$$ and $$25.0\ ^\circ\mathrm{C}$$?

Accepted Answer

$$1.25\ \mathrm{L}$$

Question 14

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

Accepted Answer

O=C=O with two lone pairs on each O

Question 15

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes of an element have the same number of protons but different numbers of neutrons.

Question 16

Which of the following is the correct name for $$\mathrm{N_2O_5}$$?

Accepted Answer

Dinitrogen pentoxide

Question 17

Which of the following is a correct statement about the energy change in an exothermic reaction?

Accepted Answer

The products have lower energy than the reactants.

Question 18

Which of the following is the correct molecular geometry for $$\mathrm{NH_3$}$$ according to VSEPR theory?

Accepted Answer

Trigonal pyramidal

Question 19

Which of the following is the correct formula for the compound formed between magnesium and nitrogen?

Accepted Answer

$$\mathrm{Mg_3N_2}$$

General Chemistry I: Comprehensive Study Notes (Practice Exam Review)

Guida di studio - Domande di pratica

Study guide - Flashcard