Chem Test 2

SnF4

Determine the empirical formula of the following compound if a sample contains 5.28 gSn and 3.37 gF;

mole

6.02 x 10^23

0.423

A 17.5 mL sample of an acetic acid (CH3CO2H) solution required 29.6 mL of 0.250 M NaOH for neutralization. The concentration of acetic acid was __________ M.

0.0102

A 31.5 mL aliquot of HNO3 (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq). It took 23.9 mL of the base to reach the endpoint of the titration. The concentration (M) of the acid was __________. 1.02 0.0051 0.0204 0.227 0.0102

79.7%

A student performs an experiment that produces 5.78 grams of silver chloride. He calculated that 7.25 grams of silver chloride should have precipitated if all of the limiting reactant reacted. What is his percent yield? 125% 20.3% 79.724% 79.7%

False

Amnomia is a strong base

(NH4)2S

Aqueous solutions of a compound did not form precipitates with Cl-, Br-, I-, SO4 2-, CO3 2-, PO4 3-, OH-, or S2-. This highly water-soluble compound produced the foul-smelling gas H2S when the solution was acidified. This compound is __________. AgNO3 Pb(NO3)2 KBr Li2CO3 (NH4)2S

0

As in As4

SnBr2 (aq) + Cu (s) → CuBr2 (aq) + Sn (s)

Based on the activity series, which one of the reactions below will occur? Pb (s) + NiI2 (aq) → PbI2 (aq) + Ni (s) SnBr2 (aq) + Cu (s) → CuBr2 (aq) + Sn (s) Mn (s) + NiCl2 (aq) → MnCl2 (aq) + Ni (s) Fe (s) + ZnCl2 (aq) → FeCl2 (aq) + Zn (s) None of the reactions will occur.

1

Br in HBrO

4

C in COCl2

46.1 amu

Calculate the formula weight of ethanol, C2H5OH.

601.93

Calculate the formula weight of the compound Ba3(PO4)2. 569.93 amu 184.30 amu 327.27 amu 601.93 amu

77.54

Calculate the percentage by mass of lead in PbCO3.

Na+ and i-

Combining aqueous solutions of BaI2 and Na2SO4 affords a precipitate of BaSO4. Which ion(s) is/are spectator ions in the reaction? Na+ and I− Ba2+ and SO42− SO42− and I− Ba2+ only Na+ only

K2CO3

Determine the empirical formula of the following compound if a sample contains 0.104 molK, 0.052 molC, and 0.156 molO;

NH2

Determine the empirical formula of the following compound if a sample contains 87.5% N and 12.5% H by mass.

61.1

How many grams of sodium chloride are there in 550.0 mL of a 1.90 M aqueous solution of sodium chloride? 122 6.11 × 104 1.05 61.1 30.5

1.31

How many moles of K+ are present in 343 mL of a 1.27 M solution of K3PO4? 0.145 1.31 11.1 0.436 3.70

1.183

How many moles of carbon dioxide are there in 52.06 g of carbon dioxide? 8.648 ×1023 1.183 6.022 × 1023 3.134 × 1025 0.8452

5.79 ×1022

How many oxygen atoms are contained in 2.74 g of Al2(SO4)3? 12 8.01 ×10−3 7.22 ×1024 6.02 ×1023 5.79 ×1022

1.08 x 10^23

How many sulfur dioxide molecules are there in 0.180 mol of sulfur dioxide? 1.08 ×1024 1.80 ×1023 1.08 ×1023 6.02 ×1024 6.02 ×1023

63.4

In a titration of 35.00 mL of 0.737 M H2SO4, __________ mL of a 0.827 M KOH solution is required for neutralization. 35.0 25.8 62.4 1.12 39.3

K2SO4

In which species does sulfur have the highest oxidation number? S8 (elemental form of sulfur) K2SO4 H2S H2SO3 SO2

7

Mn in MnO−4

-1

O in K2O2

aluminum

Of the following elements, __________ is the most easily oxidized. oxygen fluorine nitrogen aluminum gold

loss of electrons, gain of electron

Oxidation is the __________ and reduction is the __________. loss of oxygen, gain of electrons loss of electrons, gain of electrons gain of oxygen, loss of electrons gain of electrons, loss of electrons gain of oxygen, loss of mass

4

S in SO2

Ca2+,OH−

Specify what ions are present in solution upon dissolving each of the following substances in water. Ca(OH)2

H+,NO3−

Specify what ions are present in solution upon dissolving each of the following substances in water. HNO3

Zn2+,Cl−

Specify what ions are present in solution upon dissolving each of the following substances in water. ZnCl2

2NaN3(s)→2Na(s)+3N2(g)

The balanced equation for the decomposition of sodium azide is __________

2NaN3(s)→2Na(s)+3N2(g)

The balanced equation for the decomposition of sodium azide is __________. 2NaN3(s)→2Na(s)+2N2(g) 2NaN3(s)→2Na(s)+3N2(g) NaN3(s)→Na(s)+N2(g) NaN3(s)→Na(s)+N2(g)+N(g) 2NaN3(s)→Na2(s)+3N2(g)

Ca2+ (aq) + CO3 2- (aq) → CaCO3 (s)

The balanced net ionic equation for precipitation of CaCO3 when aqueous solutions of Na2CO3 and CaCl2 are mixed is __________. Na+ (aq) + Cl- (aq) → NaCl (aq) 2Na+ (aq) + CO3 2- (aq) → Na2CO3 (aq) 2Na+ (aq) + 2Cl- (aq) → 2NaCl (aq) Na2CO3 (aq) + CaCl2 (aq) → 2NaCl (aq) + CaCO3 (s) Ca2+ (aq) + CO3 2- (aq) → CaCO3 (s)

2HNO3 (aq) + Sr(OH)2 (aq) → 2H2O (l) + Sr(NO3)2 (aq)

The balanced reaction between aqueous nitric acid and aqueous strontium hydroxide is __________. HNO3 (aq) + Sr(OH)2 (aq) → H2O (l) + Sr(NO3)2 (aq) HNO3 (aq) + Sr(OH)2 (aq) → Sr(NO3)2 (aq) + H2 (g) 2HNO3 (aq) + Sr(OH)2 (aq) → Sr(NO3)2 (aq) + 2H2 (g) 2HNO3 (aq) + Sr(OH)2 (aq) → 2H2O (l) + Sr(NO3)2 (aq) HNO3 (aq) + SrOH (aq) → H2O (l) + SrNO3 (aq)

123.11

The formula of nitrobenzene is C6H5NO2. The molecular weight of this compound is __________ amu.

123.11

The formula of nitrobenzene is C6H5NO2. The molecular weight of this compound is __________ amu. 109.10 3.06 107.11 43.03 123.11

132

The formula weight of ammonium sulfate ((NH4)2SO4), rounded to the nearest integer, is __________ amu.

H+ (aq) + OH- (aq) → H2O (l)

The net ionic equation for the reaction between aqueous nitric acid and aqueous sodium hydroxide is __________. H+ (aq) + OH- (aq) → H2O (l) HNO3 (aq) + NaOH (aq) → NaNO3 (aq) + H2O (l) H+ (aq) + Na+ (aq) +OH- (aq) → H2O (l) + Na+ (aq) HNO3 (aq) + OH- (aq) → NO3 - (aq) + H2O (l) H+ (aq) + HNO3 (aq) + 2OH- (aq) → 2H2O (l) + NO3 - (aq)

a molecular compound and a strong electrolyte

The reaction between strontium hydroxide and chloric acid produces __________. a molecular compound and a strong electrolyte two molecular compounds two strong electrolytes a molecular compound and a weak electrolyte two weak electrolytes

1.00 x 10^24

The total number of atoms in 0.111 mol of Fe(CO)3(PH3)2 is __________. 1.00 ×1024 2.76 ×10−24 1.67 4.46 ×1021 15.0

100

There are __________ hydrogen atoms in 25 molecules of C4H4S2. 3.8 ×1024 1.5 ×1025 100 25 6.0 ×1025

0.752 and 0.376

What are the respective concentrations (M) of Na+ and SO42− afforded by dissolving 0.500 mol Na2SO4 in water and diluting to 1.33 L? 0.376 and 0.752 0.665 and 0.665 0.665 and 1.33 0.752 and 0.376 1.33 and 0.665

SiO2

What is the chemical formula for quartz?

148.3 amu

What is the formula weight of Mg(NO3)2?

C6H12O6

What is the molecular formula of a compound with a molar mass of 180.16 grams/mole and the empirical formula CH2O? C2H6O2 C1.5H3O1.5 C6H12O6 C2H4O

1.23

What mass (g) of AgBr is formed when 35.5 mL of 0.184 M AgNO3 is treated with an excess of aqueous hydrobromic acid? 1.23 34.5 188 1.44 53.6

375

What volume (mL) of 7.48 × 10-2 M perchloric acid can be neutralized with 115 mL of 0.244 M sodium hydroxide? 8.60 125 375 750 188

29.3

What volume (mL) of a concentrated solution of sodium hydroxide (6.00 M) must be diluted to 200.0 mL to make a 0.880 M solution of sodium hydroxide? 29.3 2.64 176 26.4 50.0

129

What volume (ml) of a 3.45 M lead nitrate solution must be diluted to 450.0 ml to make a 0.990 M solution of lead nitrate? 56 45 129 109 101

NiBr2 and AgNO3

When aqueous solutions of __________ are mixed, a precipitate forms. NaI and KBr K2SO4 and CrCl3 KOH and Ba(NO3)2 Li2CO3 and CsI NiBr2 and AgNO3

2

When the following equation is balanced, the coefficient of H2O is __________. Ca(s)+H2O(l)→Ca(OH)2(aq)+H2(g)

3

When the following equation is balanced, the coefficient of H2S is __________. FeCl3(aq)+H2S(g)→Fe2S3(s)+HCl(aq)

MgSO3

Which compound has the atom with the highest oxidation number? MgSO3 NH4Cl Al(NO2)3 Na3N CaS

Li2Co3

Which compound has the highest percentage composition of oxygen? Li2CO3 KNO3 La2O3 Al(OH)3

reactants

____appear on the left side of the equation

C

Which element is oxidized in this reaction? Fe2O3+3CO→2Fe+3CO2

Sr(OH)2, KOH, NaOH, Ba(OH)2

Which hydroxides are strong bases? Sr(OH)2 KOH NaOH Ba(OH)2 KOH, Ba(OH)2 KOH, NaOH KOH, NaOH, Ba(OH)2 Sr(OH)2, KOH, NaOH, Ba(OH)2 None of these is a strong base.

129 mL of 0.145M solution of KCl

Which solution has the same number of moles of KCl as 75.00 mL of 0.250M solution of KCl? 129 mL of 0.145M solution of KCl 25.0 mL of 0.175M solution of KCl 20.0 mL of 0.200M solution of KCl 50.0 mL of 0.125M solution of KCl 100 mL of 0.0500M solution of KCl

none of the above

With which of the following will the ammonium ion form an insoluble salt? carbonate sulfate sulfate and carbonate chloride none of the above

products

______ appear on the right side of the equation

participation reactions

cations and anions come together to form an insoluble ionic compound

oxidTION reaction

electrons are transferred from one recant to another

reduction

gain of electrons

neutralization reaction

h+ ions and OH- ions come together to from h20 molecules

k2So3

hat is the empirical formula of a compound that contains 49.4% K, 20.3% S, and 30.3% O by mass? K2SO3 KSO4 KSO3 KSO2 K2SO4

132

he formula weight of ammonium sulfate ((NH4)2SO4), rounded to the nearest integer, is __________ amu. 132 116 118 100 264

acids

ionize in aqueous solutions to form H + ions, combination of H+and an anion

oxidation

loss of electrons

nonelectrolyte

may dissolve in water but it doesn't associate into ions when it does so

molarity

measure concentration in a solution

62.4

n a titration of 35.00 mL of 0.737 M H2SO4, __________ mL of a 0.827 M KOH solution is required for neutralization. 35.0 25.8 62.4 1.12 39.3

decomposition reaction

one substance breaks down into two or more substances

combustion reaction

rapid reactions that produce a flame. involve oxygen as a reactant

bases

react with H+ ions. combination of a cation and OH-

neutralization reactions

reactions between an acid and a base

precipitate

salt falling from a solution like snow from the key

electrolyte

substance that dissociates into ions when dissolved in water

molecular weight

sum of the atomic weight of the atoms in a molecule

molar mass

the mass of 1 mol of a substance

theoretical yeild

the maximum amount of product that can be made

limiting reactant

the reactant present in the smallest stoichmetric amount

formula weight

the sum of the atomic weights of atoms in a chemical formula

combination reaction

two or more substances react to form one product