CHE151 Final Prep

Structures

100

An atom of strontium-90 contains...

__ electrons, __ protons, __ neutrons

38 electrons, 38 protons, 52 neutrons

200

What is the atomic number for an ion that has a charge of +1 and contains 19 electrons?

20

300

How many lone pairs are on the central atom of ClF₃?

2

400

What is the molecular geometry of CO₃^2-?

Trigonal Planar

500

Which of the following molecules has a 120^o bond angle?

CO₂, NH₃, IF_3, SO₃

SO₃

Ptable Trends

100

What element type is potassium?

Alkali Metal

200

What element has the highest electronegativity?

Fluorine

300

Alkaline earth metals form what charge as ions?

+2 ions.

400

Arrange the elements Li, Ne, Na, and Ar in increasing order of first ionization energy.

Na<Li<Ar<Ne

500

Arrange the species F^-, Mg²⁺, and Na⁺, in order of decreasing size.

F^->Na⁺>Mg²⁺

Reactions

100

What are the Bronsted-Lowry bases in this reaction?

NH₃(aq) + H₂O(aq) <-> NH₄⁺(aq) + OH^-(aq)

NH₃ and OH^-

200

What kind of reaction is this?

HCl(aq) + RbOH(aq) -> H₂O(l) + RbCl(aq)

Acid-Base Neutralization

300

What is the oxidation number of chlorine in NaClO₂

+3

400

What is the ΔH_rxn for CO(g) + ¹/₂O₂(g) -> CO₂(g)

C(s) + O₂(g) -> CO₂(g) ΔH_rxn=-394 kJ/mol

2C(s) + O₂(g) -> 2CO(g) ΔH_rxn=-221 kJ/mol

-284 kJ/mol

500

Use the enthalpies of formation, ΔH^o_f, in the table to determine ΔH for this reaction. 

2C₂H₂(g) + 5O₂(g) -> 4CO₂(g) + 2H₂O(g) 

ΔH^o_f kJ/mol

C₂H₂(g) = 227

H₂O(g) = -242

CO₂(g) = -393

-2510 kJ/mol