pH
4 cards- 01
What is the pH of 0.01 mol/L hydrochloric acid, a strong acid?
- A
0.01
- B
12
- C
2
- D
1
- A
- 02
What is the pH of 0.001 mol/L sodium hydroxide at 25 °C?
- A
13
- B
11
- C
3
- D
14
- A
- 03
Solution A has pH 3 and solution B has pH 5. How do their hydrogen-ion concentrations compare?
- A
A has 2 times the H⁺ concentration of B
- B
A has 100 times the H⁺ concentration of B
- C
A has 20 times the H⁺ concentration of B
- D
B has 100 times the H⁺ concentration of A
- A
- 04
What is the hydrogen-ion concentration of a solution with pH 4.5?
- A
3.2 × 10⁻⁵ mol/L
- B
1 × 10⁻⁴·⁵ is not a valid number
- C
4.5 × 10⁻⁵ mol/L
- D
5.5 × 10⁻⁵ mol/L
- A
Molar mass
1 card- 05
What is the molar mass of calcium hydroxide, Ca(OH)₂?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
58 g/mol
- B
40 g/mol
- C
74 g/mol
- D
57 g/mol
- A
Mole (unit)
2 cards- 06
How many moles of water are there in 36 g of water?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
2 mol
- B
36 mol
- C
0.5 mol
- D
18 mol
- A
- 07
What mass is 0.25 mol of sodium chloride, NaCl?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
0.25 g
- B
14.6 g
- C
234 g
- D
58.5 g
- A
Avogadro constant
2 cards- 08
How many molecules are there in 9 g of water?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
6.0 × 10²³
- B
3.0 × 10²³
- C
9
- D
5.4 × 10²⁴
- A
- 09
How many atoms are there in 1 mol of carbon dioxide, CO₂?
- A
6.0 × 10²³
- B
1.2 × 10²⁴
- C
1.8 × 10²⁴
- D
3
- A
Molar volume
2 cards- 10
Taking the molar volume of a gas as 22.4 L/mol at standard temperature and pressure, what volume does 0.5 mol of any ideal gas occupy?
- A
44.8 L
- B
11.2 L
- C
22.4 L
- D
It depends on which gas it is
- A
- 11
What is the volume of 4.4 g of carbon dioxide at STP (molar volume 22.4 L/mol)?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
2.24 L
- B
98.6 L
- C
4.4 L
- D
22.4 L
- A
Chemical equation
2 cards- 12
Balance the combustion of propane:
$$\mathrm{C_3H_8 + _,O_2 \rightarrow 3,CO_2 + 4,H_2O}$$
What is the coefficient of O₂?
- A
10
- B
3
- C
5
- D
7
- A
- 13
Balance the reduction of iron(III) oxide by carbon monoxide:
$$\mathrm{Fe_2O_3 + _,CO \rightarrow 2,Fe + _,CO_2}$$
What are the two missing coefficients?
- A
1 and 1
- B
3 and 3
- C
3 and 2
- D
2 and 2
- A
Stoichiometry
1 card- 14
$$\mathrm{2,H_2 + O_2 \rightarrow 2,H_2O}$$
How many moles of oxygen are needed to react completely with 6 mol of hydrogen?
- A
3 mol
- B
6 mol
- C
2 mol
- D
12 mol
- A
Limiting reagent
1 card- 15
$$\mathrm{2,H_2 + O_2 \rightarrow 2,H_2O}$$
6 g of hydrogen is mixed with 32 g of oxygen and the reaction goes to completion. What mass of water forms?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
18 g
- B
54 g
- C
38 g
- D
36 g
- A
Yield (chemistry)
1 card- 16
A reaction should produce 36 g of water in theory, but 27 g is collected. What is the percentage yield?
- A
9%
- B
25%
- C
133%
- D
75%
- A
Conservation of mass
1 card- 17
When 10 g of calcium carbonate is heated strongly, it decomposes completely into calcium oxide and carbon dioxide gas:
$$\mathrm{CaCO_3 \rightarrow CaO + CO_2}$$
5.6 g of solid remains. What mass of carbon dioxide was released?
- A
10 g
- B
15.6 g
- C
5.6 g
- D
4.4 g
- A
Mass fraction (chemistry)
1 card- 18
What is the percentage by mass of nitrogen in ammonium nitrate, NH₄NO₃?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
70%
- B
14%
- C
35%
- D
17.5%
- A
Empirical formula
2 cards- 19
A compound is 40.0% carbon, 6.7% hydrogen and 53.3% oxygen by mass. What is its empirical formula?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
CH₂O
- B
C₂H₄O₂
- C
C₆H₁₂O₆
- D
CHO
- A
- 20
A compound has the empirical formula CH₂O and a molar mass of 180 g/mol. What is its molecular formula?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
C₆H₁₂O₆
- B
C₂H₄O₂
- C
C₃H₆O₃
- D
CH₂O
- A
Water of crystallization
1 card- 21
What percentage of the mass of copper(II) sulfate pentahydrate, CuSO₄·5H₂O, is water?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
10%
- B
36%
- C
7%
- D
64%
- A
Molar concentration
2 cards- 22
5.85 g of sodium chloride is dissolved in water to make 500 mL of solution. What is its concentration?
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
11.7 mol/L
- B
0.2 mol/L
- C
0.05 mol/L
- D
0.1 mol/L
- A
- 23
How many moles of solute are there in 250 mL of a 0.1 mol/L solution?
- A
25 mol
- B
0.025 mol
- C
0.25 mol
- D
0.4 mol
- A
Dilution (equation)
2 cards- 24
10 mL of a 2.0 mol/L acid is diluted with water to a total volume of 100 mL. What is the new concentration?
- A
0.02 mol/L
- B
0.2 mol/L
- C
20 mol/L
- D
1.8 mol/L
- A
- 25
What volume of a 6.0 mol/L stock solution is needed to prepare 300 mL of a 0.5 mol/L solution?
- A
50 mL
- B
3.6 mL
- C
25 mL
- D
100 mL
- A
Titration
2 cards- 26
25.0 mL of hydrochloric acid is exactly neutralised by 20.0 mL of 0.100 mol/L sodium hydroxide. What is the concentration of the acid?
- A
0.080 mol/L
- B
0.100 mol/L
- C
0.002 mol/L
- D
0.125 mol/L
- A
- 27
25.0 mL of sulfuric acid is neutralised by 30.0 mL of 0.100 mol/L sodium hydroxide:
$$\mathrm{H_2SO_4 + 2,NaOH \rightarrow Na_2SO_4 + 2,H_2O}$$
What is the concentration of the acid?
- A
0.120 mol/L
- B
0.083 mol/L
- C
0.060 mol/L
- D
0.240 mol/L
- A
Acid dissociation constant
1 card- 28
Acetic acid has $K_a = 1.8 \times 10^{-5}$. What is the approximate pH of a 0.10 mol/L solution?
- A
5.0
- B
1.0
- C
2.9
- D
4.7
- A
Half-life
2 cards- 29
A radioactive isotope has a half-life of 5 days. Starting with 8 g, how long until 1 g remains?
- A
15 days
- B
20 days
- C
35 days
- D
40 days
- A
- 30
What fraction of a radioactive sample remains after four half-lives?
- A
1/16 (6.25%)
- B
1/8 (12.5%)
- C
1/4 (25%)
- D
0 (none)
- A
Radiocarbon dating
1 card- 31
Carbon-14 has a half-life of about 5,730 years. A bone contains 25% of the carbon-14 that living tissue contains. Roughly how old is it?
- A
About 1,400 years
- B
About 11,500 years
- C
About 5,700 years
- D
About 23,000 years
- A
Boyle's law
1 card- 32
A gas occupies 2.0 L at 1.0 atm. At constant temperature it is compressed to 0.5 L. What is the new pressure?
- A
0.25 atm
- B
2.0 atm
- C
4.0 atm
- D
1.5 atm
- A
Charles's law
1 card- 33
A balloon holds 1.0 L of air at 27 °C. It is warmed to 54 °C at constant pressure. What is its new volume?
- A
0.5 L
- B
2.0 L
- C
About 1.09 L
- D
1.27 L
- A
Ideal gas law
2 cards- 34
What pressure does 2.0 mol of an ideal gas exert in a 10.0 L container at 300 K? Take $R = 0.0821$ L·atm/(mol·K).
- A
4.9 atm
- B
49 atm
- C
2.5 atm
- D
0.49 atm
- A
- 35
An unknown gas has a density of 1.96 g/L at STP (molar volume 22.4 L/mol). What is it most likely to be?
- A
Nitrogen, N₂ (28 g/mol)
- B
Argon, Ar (40 g/mol)
- C
Carbon dioxide, CO₂ (44 g/mol)
- D
Oxygen, O₂ (32 g/mol)
- A
Specific heat capacity
1 card- 36
How much energy is needed to heat 100 g of water from 20 °C to 30 °C? The specific heat capacity of water is 4.18 J/(g·°C).
- A
418 J
- B
12,540 J
- C
41.8 J
- D
4,180 J
- A
Hess's law
1 card- 37
For a substance A: A → B has ΔH = −100 kJ/mol and B → C has ΔH = +30 kJ/mol. What is ΔH for A → C?
- A
−130 kJ/mol
- B
+70 kJ/mol
- C
−70 kJ/mol
- D
It cannot be found without the route
- A
Bond-dissociation energy
1 card- 38
Estimate ΔH for $\mathrm{H_2 + Cl_2 \rightarrow 2,HCl}$ from average bond enthalpies: H–H 436, Cl–Cl 243, H–Cl 432 kJ/mol.
- A
+247 kJ/mol
- B
−247 kJ/mol
- C
−185 kJ/mol
- D
+185 kJ/mol
- A
Exothermic reaction
1 card- 39
A reaction has ΔH = −92 kJ/mol. Which statement is correct?
- A
The reaction mixture gets colder as it proceeds
- B
It releases heat to the surroundings: the products have less enthalpy than the reactants
- C
It cannot happen without continuous heating
- D
It absorbs heat: the products have more enthalpy than the reactants
- A
Rate equation
1 card- 40
A reaction has the rate law rate = k[A]². If the concentration of A is doubled, what happens to the rate?
- A
It increases 8 times
- B
It doubles
- C
It stays the same
- D
It increases 4 times
- A
Equilibrium constant
1 card- 41
What is the equilibrium-constant expression $K_c$ for the Haber process?
$$\mathrm{N_2(g) + 3,H_2(g) \rightleftharpoons 2,NH_3(g)}$$
- A
$\dfrac{[\mathrm{NH_3}]}{[\mathrm{N_2}][\mathrm{H_2}]}$
- B
$\dfrac{2[\mathrm{NH_3}]}{[\mathrm{N_2}] \cdot 3[\mathrm{H_2}]}$
- C
$\dfrac{[\mathrm{N_2}][\mathrm{H_2}]^3}{[\mathrm{NH_3}]^2}$
- D
$\dfrac{[\mathrm{NH_3}]^2}{[\mathrm{N_2}][\mathrm{H_2}]^3}$
- A
Le Chatelier's principle
1 card- 42
$$\mathrm{N_2(g) + 3,H_2(g) \rightleftharpoons 2,NH_3(g)} \qquad \Delta H = -92\ \text{kJ/mol}$$
Which change shifts the equilibrium towards ammonia?
- A
Increasing the temperature
- B
Increasing the pressure
- C
Adding a catalyst
- D
Removing hydrogen
- A
Oxidation state
1 card- 43
What is the oxidation state of manganese in the permanganate ion, MnO₄⁻?
- A
−1
- B
+4
- C
+8
- D
+7
- A
Faraday's laws of electrolysis
1 card- 44
A current of 2.0 A passes through copper(II) sulfate solution for 1 hour. What mass of copper is deposited at the cathode? Faraday constant = 96,500 C/mol.
Use rounded atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40, Cu = 63.5.
- A
4.7 g
- B
9.5 g
- C
0.075 g
- D
2.4 g
- A
Redox
1 card- 45
$$\mathrm{Zn + Cu^{2+} \rightarrow Zn^{2+} + Cu}$$
Which species is the oxidising agent?
- A
Cu: it is the product of oxidation
- B
Cu²⁺: it gains electrons and is itself reduced
- C
Zn: it loses electrons
- D
Zn: it gains electrons
- A
End of deck · 45 cards