gas laws
A gas occupies 4.00 L at a pressure of 2.00 atm.
If the pressure is reduced to 1.00 atm, what will be the new volume (in L), assuming temperature is constant?
8.00 L
How much heat (in joules) is needed to raise the temperature of 50.0 g of water from 20.0°C to 30.0°C?
(Specific heat of water = 4.18 J/g·°C)
2090 J
Classify each of the following reactions as precipitation, acid–base, or redox:
a) NaOH(aq) + HCl(aq) → NaCl(aq) + H₂O(l)
b) AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)
c) Zn(s) + CuSO₄(aq) → ZnSO₄(aq) + Cu(s)
a) Acid–base (neutralization)
b) Precipitation
c) Redox
Identify which of the following are acids, bases, or neither:
HCl, NaOH, NH₃, H₂O
HCl → acid (donates H⁺ in solution)
NaOH → base (produces OH⁻)
NH₃ → weak base (accepts H⁺ to form NH₄⁺)
H₂O → amphoteric (can act as both acid and base)
What is the molarity of a solution made by dissolving 10.0 g of NaCl in enough water to make 500.0 mL of solution?
0.342 M NaCl
A balloon has a volume of 2.5 L at 27°C.
What will its volume be at 77°C, assuming constant pressure?
2.92 L.
A gas expands from 2.0 L to 5.0 L against a constant external pressure of 1.00 atm. Calculate the work done (in J) by the gas.
(1 L·atm = 101.3 J)
–304 J
Predict whether a precipitate forms when Na₂SO₄(aq) and BaCl₂(aq) are mixed.
Write the molecular and net ionic equations.
Molecular:
Na₂SO₄(aq) + BaCl₂(aq) → 2NaCl(aq) + BaSO₄(s)
Net Ionic:
Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
25.0 mL of an unknown HCl solution is completely neutralized by 30.0 mL of 0.150 M NaOH.
Find the molarity of the HCl solutio
0.180 M
How many grams of KOH are required to make 250.0 mL of 0.200 M solution?
2.81 g of KOH
A gas sample at 1.20 atm and 20°C is heated to 100°C in a sealed container.
What is the final pressure of the gas?
1.53 atm
A 50.0 g piece of metal at 100.0°C is placed in 100.0 g of water at 25.0°C.
The final temperature of the system is 30.0°C.
Find the specific heat of the metal.
(Specific heat of water = 4.18 J/g·°C)
0.597 J/g⋅°C
Write the balanced molecular, total ionic, and net ionic equations for the reaction between HCl(aq) and NaOH(aq).
Molecular:
HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l)
Total Ionic:
H⁺(aq) + Cl⁻(aq) + Na⁺(aq) + OH⁻(aq) → Na⁺(aq) + Cl⁻(aq) + H₂O(l)
Net Ionic:
H⁺(aq) + OH⁻(aq) → H₂O(l)
What volume of 0.250 M H₂SO₄ is required to completely neutralize 50.0 mL of 0.500 M NaOH?
50.0 mL of H₂SO₄
What volume of 0.150 M H₂SO₄ contains 0.0300 mol H₂SO₄?
200 mL
A 2.00 L sample of nitrogen at 1.00 atm and 25°C is compressed to 1.50 L and cooled to 10°C.
What is the new pressure of the gas?
1.27 atm.
A 25.0 g piece of aluminum at 95.0°C is placed into 100.0 g of water at 22.0°C.
If the final temperature is 25.0°C, find the specific heat of aluminum.
(c₍water₎ = 4.18 J/g·°C)
0.716 J/g⋅°C
In the reaction below, determine which species is oxidized and which is reduced as well as reducing and oxidizing agents:
2Fe²⁺(aq) + Cl₂(g) → 2Fe³⁺(aq) + 2Cl⁻(aq)
Fe²⁺ → Fe³⁺ (oxidized, loses e⁻)
Cl₂ → 2Cl⁻ (reduced, gains e⁻)
➡️ Fe²⁺ is the reducing agent, Cl₂ is the oxidizing agent.
Determine which element is oxidized and which is reduced in the reaction as well as oxidizing agent and reduction agent
2Al(s) + 3Cu²⁺(aq) → 2Al³⁺(aq) + 3Cu(s)
Al: 0 → +3 → oxidized
Cu²⁺: +2 → 0 → reduced
➡️ Al is the reducing agent, Cu²⁺ is the oxidizing agent
You have 100.0 mL of 2.00 M HCl, and you dilute it to 500.0 mL total volume.
What is the new concentration?
0.400 M
A 5.0 g sample of O₂ gas is confined in a 3.00 L container at 27°C.
Find the pressure in atm.
1.28 atm.
A 40.0 g piece of iron at 200°C is dropped into 60.0 g of copper at 25°C inside an insulated container.
If the final temperature is 45.0°C, find the specific heat of iron.
(c₍Cu₎ = 0.385 J/g·°C)
0.0745 J/g⋅°C
When Pb(NO₃)₂(aq) reacts with KI(aq), a yellow precipitate forms.
Write the balanced molecular, total ionic, and net ionic equations, and identify the precipitate
Molecular:
Pb(NO₃)₂(aq) + 2KI(aq) → 2KNO₃(aq) + PbI₂(s)
Total Ionic:
Pb²⁺(aq) + 2NO₃⁻(aq) + 2K⁺(aq) + 2I⁻(aq) → 2K⁺(aq) + 2NO₃⁻(aq) + PbI₂(s)
Net Ionic:
Pb²⁺(aq) + 2I⁻(aq) → PbI₂(s)
Balance the following redox reaction in acidic solution:
MnO₄⁻ + Fe²⁺ → Mn²⁺ + Fe³⁺
MnO4−+8H++5Fe2+→Mn2++5Fe3++4H2O
25.0 mL of H₂SO₄ is required to neutralize 35.0 mL of 0.250 M NaOH.
What is the molarity of the H₂SO₄?
Reaction: H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O
Molarity of H₂SO₄ = 0.175 M