$$\frac{40}{50} \times 100 = 80\%$$

Question 1

Which of the following statements correctly describes the difference between ionic and covalent bonds?

Accepted Answer

Covalent bonds involve the sharing of electrons between atoms, while ionic bonds involve the transfer of electrons from one atom to another.

Question 2

Which factor increases the lattice energy of an ionic compound?

Accepted Answer

Increasing the charge of the ions and decreasing the radius of the ions.

Question 3

Given the empirical formula CH$$_2O $$and a molar mass of 180 g/mol, what is the molecular formula?

Accepted Answer

C$$_6H$_{12}O$_6$$

Question 4

Which of the following ions is a polyatomic ion?

Accepted Answer

OH$$^-$$

Question 5

What is the percent yield if the theoretical yield is 50 g and the actual yield is 40 g?

Accepted Answer

$$\frac{40}{50} 	imes 100 = 80\%$$

Question 6

Which of the following best explains why double bonds are shorter and stronger than single bonds?

Accepted Answer

Double bonds involve more shared electrons, increasing the electrostatic attraction between atoms.

Question 7

A sample contains 84.1 g of carbon and 15.9 g of hydrogen. What is the empirical formula?

Accepted Answer

CH$$_2$$

Question 8

Which of the following is the correct formula and charge for the permanganate ion?

Accepted Answer

MnO$$_4^-$$

Question 9

Which statement about lattice energy is correct?

Accepted Answer

Lattice energy increases as the charge of the ions increases and the radius decreases.

Question 10

What is the charge on the iron ion in FeCl$$_3$$?

Accepted Answer

3+

Question 11

Which of the following is NOT a correct step in calculating an empirical formula from percent composition?

Accepted Answer

Add the percent composition values together to get the empirical formula.

Question 12

Which term describes the energy released when one mole of an ionic compound forms from its free ions in the gas phase?

Accepted Answer

Lattice energy

Question 13

Which of the following is the correct formula and charge for the acetate ion?

Accepted Answer

CH$$_3$$COO$$^-$$

Question 14

Which of the following is a correct statement about polyatomic ions?

Accepted Answer

Polyatomic ions are charged groups of more than one kind of atom joined together by covalent bonds.

Question 15

If a compound contains 6 moles of carbon, 12 moles of hydrogen, and 6 moles of oxygen, what is its empirical formula?

Accepted Answer

CH$$_2O$$

Question 16

Which of the following is the correct formula and charge for the cyanide ion?

Accepted Answer

CN$$^-$$

Question 17

Which of the following is true about the relationship between the charge and radius of ions and the melting point of an ionic solid?

Accepted Answer

Higher charge and smaller radius lead to higher melting points.

Question 18

Which of the following is the correct formula and charge for the hydroxide ion?

Accepted Answer

OH$$^-$$

Question 19

Which of the following is the correct formula and charge for the phosphate ion?

Accepted Answer

PO$$_4$$^{3-}$$

Question 20

Which of the following best describes a molecule?

Accepted Answer

A unit of matter that results when two or more atoms are joined by covalent bonds.

Chapter 4: Molecules and Compounds – Study Notes

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