Organic Chemistry Exam 2 - Timberlake

2Mg + O2 --> 2MgO The number of moles of MgO produced when 0.20 moles of O2 reacts completely is

0.40 moles

What is the [H3O+] in a solution with [OH-] = 1 x 10-12 M?

1 x 10-2 M

What is the molar mass of copper (II) sulfate, CaSO4?

159.6g

2Mg + O2 --> 2MgO The number of oxygen moles needed to react with 4.o of Mg is

2.0 moles

How many moles of water, H2O, are present in 75.0g H2O?

4.17 moles

2Mg + O2 --> 2MgO In the reaction of nitrogen gas, N2, with hydrogen gas, H2, to form and ammonia gas, NH3, how many moles of hydrogen are needed to react with two moles of nitrogen?

6 moles

How many grams of Fe2O3 are there in 0.500 moles of Fe2O3?

79.8g

What is the pH of a solution with [H3O+] = 1 x 10-9 M?

9.0

Which of the following is a buffer system? A) H2O and HCl B) NaCl and NaNO3 C) H2CO3 and KHCO3 D) NaCl and NaOH E) Hal and NaOH

C) H2CO3 and KHCO3

What is the formula of carbon tetraiodide?

CI4

Which of the following correctly gives the best coefficients for the reaction below? N2H4 +H2O2 --> N2 + H20 A) 2, 4, 2, 8 B) 1, 1, 1, 1 C) 2, 4, 2, 4 D) 1, 4, 1, 4 E) 1, 2, 1, 4

E) 1, 2, 1, 4

Which of the following statements correctly describes the hydronium-hydroxide balance in the given solution?

In bases, [OH-] is greater than [H3O+]

2Mg + O2 --> 2MgO Iron metal reacts with oxygen gas to produce iron (III) oxide. What will be the effect of adding more oxygen gas in a closed reaction vessel?

More iron oxide will be produced.

According to Broasted-Lowry definition

a base is a proton acceptor.

The solubility of KI is 50g in 100g of H2O at 20°C. If 110g of KI are added to 200 grams of H2O,

a saturated solution will form.

According to naming rules, the types of compounds that use prefixes in their names are

covalent compounds.

The correct name for the compound N2O3 is

dinitrogen trioxide.

A reaction that releases energy as it occurs is classified as a(n) ____.

exothermic reaction

The ____ is the energy difference between reactants and products in a chemical reaction.

heat of reaction

If the reaction below is exothermic, the energy level of the reactants is ____. H2 + O2 --> 2H2O

higher than that of the products

An increase in the temperature of a solution usually

increases solubility of a solid solute in the solution.

Strong electrolytes dissolve in water to produce ____.

ions

Weak electrolytes dissolve in water to produce ____ and ____.

ions, molecules

Nonelectrolytes dissolve in water to produce ____.

molecules

An acid and base react to form a salt and water in a(n) ____ reaction.

neutralization

The shape of the ammonia molecule (NH3) is

pyramidal.

When some of the sugar added to iced tea remains undissolved at the bottom of the glass, the solution is

saturated.

In an oxidation-reduction reaction, the substance oxidized always

shows a loss of electrons.

In a buffer system of HF and its sat, NaF,

the HF neutralizes added base.

When KCl dissolves in water

the K+ ions are attracted to the partially negative oxygen atoms of the water molecule.

The ____ is the minimum energy needed for a chemical reaction to begin.

activation energy