Question 1

Which of the following best describes the difference between an ionic bond and a covalent bond?

Accepted Answer

Ionic bond: transfer of electrons from a metal to a nonmetal; Covalent bond: sharing of electrons between two nonmetals.

Question 2

Which of the following elements exists naturally as a diatomic molecule?

Accepted Answer

Oxygen ($$\mathrm{O_2$})$$

Question 3

What is the total number of electrons shared in a triple covalent bond?

Accepted Answer

$$6$$

Question 4

Which of the following best explains why covalent compounds generally do not conduct electricity in water?

Accepted Answer

They are composed of molecules that do not dissociate into ions.

Question 5

How many charge clouds (bonds + lone pairs) are around the central atom in $$\mathrm{NH_3$}$$, and what is its molecular shape?

Accepted Answer

$$4$$ charge clouds; trigonal pyramidal

Question 6

Which molecule is polar due to both its bond polarity and its molecular shape?

Accepted Answer

$$\mathrm{H_2O}$$

Question 7

Given the electronegativity values: $$\mathrm{Cl}$$ ($$3.0) $$and $$\mathrm{H}$$ ($$2.1$$), what type of bond is present in $$\mathrm{HCl}$$?

Accepted Answer

Polar covalent

Question 8

Which of the following is the correct name for $$\mathrm{N_2O_4}$$?

Accepted Answer

Dinitrogen tetraoxide

Question 9

Balance the following chemical equation: $$\mathrm{C_2H_6} + \mathrm{O_2$} \rightarrow \mathrm{CO_2$} + \mathrm{H_2O}. $$What are the correct coefficients?

Accepted Answer

$$2, 7, 4, 6$$

Question 10

Which of the following reactions is a redox reaction?

Accepted Answer

$$\mathrm{Zn} + \mathrm{$$CuSO_4$$} \rightarrow \mathrm{$$ZnSO_4$$} + \mathrm{Cu}$$

Question 11

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

Accepted Answer

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

Question 12

Which statement about acids and bases is correct?

Accepted Answer

Acids produce $$\mathrm{H^+}$$ ions in water; bases produce $$\mathrm{OH^-}$$ ions.

Question 13

A solution contains $$\mathrm{$$BaCl_2$$}$$ and $$\mathrm{Na_2SO_4}. $$According to solubility rules, what precipitate will form?

Accepted Answer

$$\mathrm{$$BaSO_4$$}$$

Question 14

Which of the following best describes the role of an oxidizing agent in a redox reaction?

Accepted Answer

It gets reduced and gains electrons.

Question 15

Which of the following molecules is nonpolar despite having polar bonds?

Accepted Answer

$$\mathrm{CO_2$}$$

Question 16

What is the partial charge on the more electronegative atom in a polar covalent bond?

Accepted Answer

$$\delta^- ($$partial negative)

Question 17

Which of the following is the correct molecular formula for a compound named 'carbon tetrachloride'?

Accepted Answer

$$\mathrm{$$CCl_4$$}$$

Question 18

Which of the following best describes the law of conservation of mass in a chemical reaction?

Accepted Answer

The total mass of reactants equals the total mass of products; atoms are neither created nor destroyed.

Question 19

Which of the following is a correct example of an acid-base reaction?

Accepted Answer

$$\mathrm{$$HNO_3$$} + \mathrm{KOH} \rightarrow \mathrm{$$KNO_3$$} + \mathrm{H_2O}$$

GOB Chemistry Study Notes: Covalent Bonding, Molecular Structure, and Chemical Reactions

Guida di studio - Domande di pratica

Study guide - Flashcard