Chapter 4

Question 1

Write a dissociation equation for ammonium sulfate
in water, and predict what amount (mol) of each ion
will form from 5.0 mol of ammonium sulfate.

Answer 1

dissociation equation: (NH4)2SO4(s) —> 2NH4+ (aq) + SO42- (aq)
10 mols of NH4+
5 mols of SO42-

Question 2

how do you find molarity?

Answer 2

mol/L

Question 3

What is the molarity of an aqueous solution that contains
0.715 mol of glycine (H2NCH2COOH) in 495 mL?

Answer 3

1.44 M of glycine

Question 4

How many grams of solute are in 1.75 L of 0.460 M
sodium monohydrogen phosphate buffer solution?

Answer 4

114g Na2HPO4

Question 5

“Isotonic saline” is a 0.15 M aqueous solution of NaCl. How
would you prepare 0.80 L of isotonic saline from a 6.0 M
stock solution?

Answer 5

0.020 L
to prepare the solution, you would take 0.020 L of 6.0M stock and add 0.78L of water to get 0.80L of the 0.15M solution

Question 6

Calculate the final volume (L) of a 0.0700 M solution
prepared by diluting 18.0 mL of 0.155 M lithium
carbonate with water

Answer 6

0.0399 L

Question 7

In a simulation mercury removal from industrial wastewater,
0.050 L of 0.010 M mercury(II) nitrate reacts with 0.020 L of
0.10 M sodium sulfide to form mercury(II) sulfide and sodium
nitrate. How many grams of mercury(II) sulfide form?

Answer 7

0.12 g HgS

Question 8

why is PbI2 insoluble?

Answer 8

because there is a stronger electrostatic attraction than water

Question 9

are group 1A and NH4+ compounds insoluble or soluble?

Answer 9

soluble

Question 10

nitrates, acetates, chlorates. insoluble or soluble?

Answer 10

soluble

Question 11

chlorides, bromides, iodides. insoluble or soluble?

Answer 11

soluble

Question 12

Ag+, Pb2+, Cu+, Hg2+, Hg22+. insoluble or soluble?

Answer 12

insoluble

Question 13

flourides. insoluble or soluble?

Answer 13

soluble

Question 14

Pb2+, group 2A. insoluble or soluble?

Answer 14

insoluble

Question 15

sulfates. insoluble or soluble?

Answer 15

soluble

Question 16

hydrogen carbonates. insoluble or soluble?

Answer 16

soluble

Question 17

carbonates, chromates, and phosphates. insoluble or soluble?

Answer 17

insoluble

Question 18

sulfides. insoluble or soluble?

Answer 18

insoluble

Question 19

Na2CO3. insoluble or soluble?

Answer 19

soluble because Na2 is in group 1A

Question 20

NH4OH. insoluble or soluble?

Answer 20

soluble because NH4 is soluble

Question 21

Co(NO3)3. insoluble or soluble?

Answer 21

soluble because nitrate is soluble

Question 22

Pb2CO3. insoluble or soluble?

Answer 22

insoluble because carbonate is insoluble

Question 23

Mg(OH)2. insoluble or soluble?

Answer 23

insoluble because hydroxide is insoluble

Question 24

AgHCO3. insoluble or soluble?

Answer 24

soluble because all bicarbonates are soluble

Question 25

How many H+(aq) ions are in 25.3 mL of 1.4 M nitric acid?

Answer 25

2.13 x 10^22 H+ ions

Question 26

what causes a reaction to be double displacement

Answer 26

when the cations switch places

Question 27

A 50.00 mL sample of HCl is titrated with 0.1524 M NaOH. The buret reads 0.55 mL at the start and 33.87 mL at the end point. Find the molarity of the HCl solution.

Answer 27

0.1016M HCl

Question 28

oxidation is

Answer 28

the loss of electrons, making it more positive

Question 29

reduction is

Answer 29

the gain of electrons, making it more negative

Question 30

what does a redox reaction involve

Answer 30

an electron transfer

Question 31

O.N. for a monoatomic ion

Answer 31

the ions charge

Question 32

O.N. for an atom is its elemental form( Na, O2, Cl2, etc.)

Answer 32

0

Question 33

O.N. for group 1A

Answer 33

+1

Question 34

O.N. for group 2A

Answer 34

+2

Question 35

O.N. for fluorine

Answer 35

-1

Question 36

O.N. for hydrogen

Answer 36

+1 when bound to non metals, and -1 when bonded to metals and boron

Question 37

O.N. for oxygen

Answer 37

-2, and -1 when in peroxides(H2O2, Na2O2)

Question 38

O.N. for Cl, Br, and I

Answer 38

-1 except when bound to O and with other halogens with the smaller period number, BrCl3: Cl = -1 and Br = +3 (bigger is positive, smaller is negative)

Question 39

what type of reaction is C6H14(l) + O2(g) --> CO2(g) +H2O(g)

Answer 39

combustion reaction