Question 1

Which of the following correctly represents the formula for the ionic compound formed between magnesium and nitrate ions?

Accepted Answer

$$\mathrm{Mg(NO_3$)_2}$$

Question 2

Which of the following best describes the difference between an atom and an ion?

Accepted Answer

An ion has a different number of electrons than protons, while an atom has equal numbers of protons and electrons.

Question 3

What is the correct name for the compound $$\mathrm{N_2O_5}$$?

Accepted Answer

Dinitrogen pentoxide

Question 4

Which of the following best explains why water ($$\mathrm{H_2O}) is a $$polar molecule?

Accepted Answer

It has polar bonds and a bent molecular geometry, resulting in a net dipole moment.

Question 5

A solution is prepared by dissolving 0.50 mol of NaCl in enough water to make 250 mL of solution. What is the molarity of the solution?

Accepted Answer

$$2.0\ \mathrm{M}$$

Question 6

Which of the following intermolecular forces is responsible for the high boiling point of water compared to methane ($$\mathrm{CH_4$}$$)?

Accepted Answer

Hydrogen bonding

Question 7

How many moles of oxygen atoms are present in 1 mole of ethanol ($$\mathrm{C_2H_5OH}$$)?

Accepted Answer

1

Question 8

Which of the following correctly describes the electron domain geometry and molecular geometry of ammonia ($$\mathrm{NH_3$}) $$according to VSEPR theory?

Accepted Answer

Electron domain geometry: tetrahedral; Molecular geometry: trigonal pyramidal

Question 9

A student needs to prepare 100.0 mL of a 0.250 M NaCl solution from a 1.00 M NaCl stock solution. What volume of the stock solution should be used?

Accepted Answer

$$25.0\ \mathrm{mL}$$

Question 10

Which of the following best describes the process of a precipitation reaction?

Accepted Answer

Positive and negative ions in solution combine to form an insoluble solid.

Question 11

What is the molar mass of ammonium sulfate, $$\mathrm{(NH_4$)_2SO_4}$$? (Atomic masses: N = 14, H = 1, S = 32, O = 16)

Accepted Answer

$$132\ \mathrm{g/mol}$$

Question 12

Which of the following is the correct formula for phosphoric acid?

Accepted Answer

$$\mathrm{H_3PO_4}$$

Question 13

A sample of ethanol ($$\mathrm{C_2H_5OH}) $$has a mass of 46.0 g. How many molecules of ethanol are present in the sample? (Molar mass of $$\mathrm{C_2H_5OH} = 46.0 g/$$mol)

Accepted Answer

$$6.022 	imes 10$$^{23}$$

Question 14

Which of the following best describes the difference between sigma ($$\sigma) $$and pi ($$\pi) $$bonds?

Accepted Answer

A sigma bond is formed by head-on overlap of orbitals, while a pi bond is formed by side-to-side overlap.

Question 15

Which of the following is the correct name for $$\mathrm{$$FeCl_3$$}$$?

Accepted Answer

Iron(III) chloride

Question 16

A reaction releases 241.8 kJ of heat when 1 mole of $$\mathrm{H_2$}$$ reacts. What is the enthalpy change ($$\Delta H) $$for the reaction $$2\ \mathrm{H_2$} + \mathrm{O_2$} \rightarrow 2\ \mathrm{H_2O}$$?

Accepted Answer

$$-483.6\ \mathrm{kJ}$$

Question 17

Which of the following best explains why sodium chloride ($$\mathrm{NaCl}) $$dissolves in water?

Accepted Answer

Ion-dipole attractions between $$\mathrm{Na^+}$$/$$\mathrm{Cl^-}$$ ions and water molecules overcome the ionic lattice energy.

Question 18

Which of the following is the correct formula for the compound formed between aluminum and sulfate ions?

Accepted Answer

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

Question 19

A 50.0 mL sample of a 6.0 M HCl solution is diluted to a final volume of 300.0 mL. What is the final concentration?

Accepted Answer

$$1.0\ \mathrm{M}$$

Question 20

Which of the following best describes the relationship between density, mass, and volume?

Accepted Answer

$$\mathrm{Density} = \frac{\mathrm{Mass}}{\mathrm{Volume}}$$

CHEM 111 Study Guide: Naming, Representing, and Quantifying Particles in Matter

Guida di studio - Domande di pratica

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