CHEM 1008; all quizzes

the same types of intermolecular forces

"Like dissolve like" refers to compounds with...

NaOH and KOH can burn your skin and eyes or damage your clothing

.true

AgNO3 can stain your skin and clothing.

..true

For a saturated NaCl solution, how would heating this solution affect the equilibrium?

shift right

What is the common ion effect? How might I use the common ion effect in the previous equation to reduce the amount of Pb+2 in solution?

the common ion effect = if the concentration of any ion is increased by adding the same common ion, the equilibrium will shift in the direction to counteract the change. an ion on the opposite side of Pb+2 could be decreased for reduction of Pb2+ concentration?

HCl and HNO3 can burn your skin and eyes or damage your clothing.

true

hydrogen bond

A special case of dipole-dipole interaction between an electronegative atom and a hydrogen atom bonded to another electronegative atom, particularly F, O, or N, is known as a...

Which one of the following substances has London dispersion force as its only intermolecular force? a. H2S b. CH3OH c. NH3 d. CH4

CH4

Dipole-dipole forces exist between neutral and polar molecules.

FALSE!

The order of the reaction can be determined by the stoichiometry of the equation.

False

This same Coke is canned under a pressure of carbon dioxide. This is an example of Henry's Law. How does an increase or decrease in the pressure affect the solubility of the carbon dioxide?

Increase pressure: Increase solubility Decrease pressure: Decrease solubility

For the following reaction choose the equilibrium expression: HA(aq) + H2O(l) ⇔ H3O+(aq) + A-(aq)

Ka=[A_][H3O+]/[HA]

Write the solubility expression for the following equation.Given that the solubility constant for the following reaction is Ksp = 9.8 × 10-9, calculate the concentration of Pb+2 in this solution once it reaches equilibrium. PbI2(s) « Pb+2(aq) + 2 I-(aq)

Ksp= [Pb2+][I_]2; [Pb]=2.6 x 10-3 M

Choose the equilibrium equation for a saturated NaCl solution.

NaCl(s) + H2O(l) → Na(aq) + Cl(aq)

When disposing of waste metal solutions, you should: Select one:

Place it in an appropriately labeled bottle.

Mixing strong acids and bases can result in a violent, explosive reaction. In this lab, an acid and base are mixed together. This procedure is safe because

The acids and bases used are dilute.

The rate of vaporization increases with... a. increasing temperature b. increasing exposed surface area c. decreasing strength of intermolecular forces d. all of these

d. all of these

The answer to the previous question is not an oxidation/reduction reaction because there in no transfer of ___

electrons

Of the following, which should NOT be disposed of in the drain? a. Water b. hexane c. NaCl

hexane

Van't Hoff's factor

moles of particles in solution/moles of solute dissolved; 1

A substance will have stronger London dispersion forces if it has... a. more electrons b. polar bonds c. a hydrogen bonded oxygen d. fewer electrons

more electrons

For a saturated NaCl solution, what effect will adding concentrated HNO3 have on the system?

no effect

Which of the following should NOT go in the glass waste bin (choose all that are correct)? Select one or more: a. Used gloves b. Chemicals c. Broken glass d. Paper

used gloves chemicals paper

If 45 grams of NaCl are dissolved in 750 ml of water, what is the molarity and molality of the resulting solution? Assume the density of the water is 1.005 g/ml . Na = 22.99g/mole and Cl = 35.45 g/mole.

1.02 1.02

A 50.0 mL sample of unknown hydrochloric acid solution is titrated with 0.203 M NaOH. The equivalence point was reached after the addition of 37.8 mL NaOH. What is the concentration of the original HCl solution? Round your answer to three decimal places.

1.53

Why must the reaction analysis be done promptly on mixing the reactants?

As time passes the reaction goes to completion affecting the analysis.

All of the following are oxidation/reduction reactions except: a. Combustion reaction [ex: CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g)] b. Tarnishing [ex: 2 Ag(s) + S(g) → Ag2S(s)] c. Rusting [ex: 4 Fe(s) + 3 O2(g) → 2 Fe2O3(s)] d. Acid/Base neutralization [ex: NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)]

Acid/Base neutralization [ex: NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)]

Identify the oxidation state of each of the elements in the following chemical equations. Identify what is oxidized and what is reduced in the same equations. a. H2(g) + O2(g) → H2O(g) b. Cu2+(aq) + Zn(s) → Cu(s) + Zn2+(aq)

H2: 0 to +1; OXIDIZED O2: 0 to -2; REDUCED Cu2+: 2+ to 0; REDUCED Zn2+; 0 to 2+; OXIDIZED

Identify the diprotic acid from the below list Select one: a. NaOH b. Ba(OH)2 c. Mg(OH)2 d. H2CO3 e. HF f. HCOOH

H2CO3

Identify the strong acid from the following list. a. HBr b. H3PO4 c. Mg(OH)2 d. CH3COOH e. HF f. NaOH

HBr

What is the acid catalyst in the reaction we will examine today?

HCl/hydrochloric acid

What is responsible for the purplish color observed in today's lab?

I2/Iodine

What is Le Chatelier's Principle?

If a chemical system at equilibrium experiences a change in concentration, temperature, volume, or partial pressure, then the equilibrium shifts to counteract the imposed change.

We will use which of the following equations in today's lab?

Rate of Reaction = k [acetone]a[iodine]i[HCl]h

For a saturated NaCl solution, what effect will adding concentrated HCl have on the system?

Shift left

What is a buffered solution?

Solutions that contain both a weak acid and it's conjugate base, or a weak base and it's conjugate acid. While most solutions change pH rapidly when either acid or base is added, a buffer solution resists pH change by neutralizing the added acid or added base.

Coke has 39 grams of sugar dissolved in 355 mL of water. Define the following and provide an example from this can of Coke. a. Solvent b. Solute c. Van't Hoff's factor

Solvent - The majority component of a solution; Water Solute - The minority component of a solution; Sugar Van't Hoff's factor - moles of particles in solution/moles of solute dissolved; 1

higher melting/boiling pts.

Substances with stronger intermolecular attractions have...

All substances experience intermolecular attractions.

TRUE

Which of the following is true of intermolecular forces? a. The forces that exist within a molecule. b. The strongest force in chemistry. c. The forces that exist between molecules. d. The force that bonds hydrogen with oxygen.

The forces that exist between molecules.

solvent

The majority component of a solution; Water

Solute

The minority component of a solution; Sugar

Hydrogen Bonding

What is the predominant intermolecular in water?

An acid (select all that apply): a. can cause skin burns b. can cause eye injuries c. can be disposed of in the drain without dilution d. can react violently with a base e. can be used to treat a skin rash

can cause skin burns can cause eye injuries can react violently with a base