Chemistry SI Exam 2 Review

Miscellaneous (Unit 1 and 2)

100

What is group 17?

Halogens

200

Groups 3-12

What are transition metals?

300

ion with a 3+ charge, 28 electrons and a mass number of 71

What is Ga³⁺

400

Bromine has two naturally occurring isotopes. The moist abundant isotope (50.69%) is 79/35Br of mass 78.9183 amu. What is the other isotope?

81/35 Br

500

Which is not named correctly?

a) MnO₄ Manganese(II) oxide

b) CuSO₄ copper(II) sulfate

c) Na₃PO₄ sodium phosphate

d0 CaF₂ calcium fluoride

A is incorrect. (MnO₄)

Unit 3-Empirical and Molecular Formulas

100

What is the mass percent of oxygen in Fe₂(SO₄)₃?

58.5%

200

How many hydrogen atoms are in 2.50 g of pharmacolite, CaHAsO₄*2H₂O (Molar mass= 216.0)?

3.48 x 10²²

300

1.00 g of hydrated potassium carbonate, K₂CO₃*nH₂O, is heated to 250 C to give 0.836 g anhydrous K₂CO₃. What is the value of n?

1.5

(0.164 g H₂O) * (1 mol H₂O/18.0 g H₂O) = 0.0091 mol H₂O

(0.836 g K₂CO₃) * (1 mol K₂CO₃/138 g K₂CO₃) = 0.0060 mol K₂CO₃

Divide both sides by 0.0060.

400

What is the empirical formula of a compound of carbon, hydrogen, and oxygen that contains 51.56% carbon and 14.09% hydrogen by mass?

C₄H₁₃O₂

500

An organic compound contains only carbon, hydrogen, nitrogen, and oxygen. It is 61.71% C, 4.03% H, and 16.00% N by mass. What is its empirical formula?

C₉H₇N₂O₂

Unit 3-Molarity

100

What is the molarity of 98.0 g of H₃PO₄ in 1.00 L of solution?

1.00 M

200

2.50 g of carbon dioxide contains ___ oxygen atoms.

6.80x10²³

300

Determine the number of atoms and the mass of zirconium, silicon, and oxygen found in 0.3384 mol of zircon, ZrSiO₄.

zirconium: 2.03x10²³ atoms; 30.87 g

silicon: 2.038x10²³ atoms; 9.504 g

oxygen: 8.151x10²³ atoms; 21.66 g

400

What is the molarity of 1.49 kg of C₃H₇OH, in 2.50 L of solution?

9.92 M

500

What is the concentration of a H₃PO₄ solution that results when 2.35 L of a 0.350 M solution is diluted to a final volume of 4.00 L?

0.206 M

Unit 4-Balancing Equations

100

Which compound will react with aqueous potassium carbonate to form a precipitate? Iron(III) chloride, ammonium acetate or lithium phosphate?

iron(III) chloride

200

What are the smallest whole number coefficients for each substance in the chemical reaction when balanced?

NaBr + Cl₂ ---> NaCl + Br₂

2, 1, 2, 1

300

Balance: 
Cu(s)+HNO3(aq)⟶Cu(NO3)2(aq)+H2O(l)+NO(g)

3Cu(s)+8HNO3(aq)⟶3Cu(NO3)2(aq)+4H2O(l)+2NO(g)

400

Balance: NH₄NO₃ ---> N₂ + O₂ + H₂O

2NH₄NO₃ ---> 2N₂ + O₂ + 4H₂O

500

Write a balanced chemical equation for the combustion of ethan gas, C₂H₆

2C₂H₆(g) + 7O₂(g) ---> 4CO₂(g) + 6H₂O(l)

Unit 4-Solubility

100

Is Group 1A soluble?

Yes, group 1A (Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺) is soluble, no exceptions.

200

Which of the following salts are insoluble?

a) LiCl

b) NaCl

c) AgCl

d) KCl

c) AgCl

300

Which compound is soluble: potassium sulfate or barium sulfate.

potassium sulfate

400

Is sulfuric acid soluble?

Yes, H₂SO₄ is a strong acid

500

What is/are the spectator ion(s) in this reaction?

HC₂H₂O₂ + NaOH ---> NaC₂H₂O₂ + H₂O

Na⁺ and C₂H₃O₂^-