Quiz chem 1120 review; 2024

A section of the Periodic Table containing main group elements is shown. If the elements W, X, Y, and Z have electronegativity values of 1.0, 2.0, 2.5, and 3.5, respectively, which bond is ionic?

A section of the Periodic Table containing main group elements is shown. If the elements W, X, Y, and Z have electronegativity values of 1.0, 2.0, 2.5, and 3.5, respectively, which bond is ionic?

WZ

Which molecule will undergo only London dispersion forces when interacting with other molecules of the same kind?

 

C₄H₁₀

Which statement best describes the way a catalyst works?

 

It decreases the value of E_act.

Which of the following cannot have hydrogen bonds?

HCl

Which factors would increase the rate of a chemical reaction?

I.	Increasing the temperature

II.	Removing products as they are formed

III.	Adding a catalyst

I, II, and III

Which pair of molecules has the strongest dipole-dipole interactions?

 

NH₃ and NH₃

Which change to this reaction system would cause the equilibrium to shift to the right?

N₂(g) + 3 H₂(g) 2 NH₃(g) + heat

 

lowering the temperature

C₅H₅N + H₂CO₃ C₅H₆N⁺ + HCO₃^-
In the reaction shown, the conjugate acid of C₅H₅N is

 

C₅H₆N⁺.

A necessary requirement for a Brønsted base is

 

a lone pair of electrons in its Lewis dot structure.

In the following equation, which of the following is acting as the Bronsted acid?

HClO₄ + H₂O → ClO₄^- + H₃O⁺

 

HClO₄

Write the equilibrium expression for the following reaction:

4 HNO₃(l) 4 NO₂(g) + 2 H₂O(g) + O₂(g)

 

[NO₂]⁴ [H₂O]² [O₂]

Consider the reaction:

2 CO(g) + O₂(g) 2 CO₂(g)

The equilibrium expression for this reaction is:

Hydrogen cyanide, HCN, is a weak acid. Which equation best represents its aqueous chemistry?

HCN(aq) + H₂O(l) CN^-(aq) + H₃O⁺(aq)

A bond where the electrons are shared equally is called a(an) ________ bond.

 

nonpolar covalent

A Brønsted-Lowry base is a substance which

 

accepts protons from other substances.

Consider the reaction shown:

452 kcal + 4 PCl₅(s) → P₄(s) + 10 Cl₂(g)

This reaction is ________ because the sign of ΔH is ________.

 

endothermic; positive

Given the following reaction, the equilibrium expression will be:

C(s) + 2 H₂(g) CH₄(g)

[CH4]/[H2]2

Consider the reaction shown:

C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O + 488 kcal

We can say that this reaction is ________ and that the sign of ΔH is ________.

 

exothermic; negative

In the reaction energy diagrams shown, reaction B is ________, and it occurs ________ reaction B.

 

endergonic; faster than

Based on the reaction shown, which statement is true?

S + O₂ → SO₂ + 70.8 kcal

 

70.8 kcal are produced when 32.1 g of sulfur reacts.