Chemical equations and stoichiometry calculations - One Line Questions
1.
If 100 mL of a 0.1 M HCl solution is mixed with 100 mL of a 0.1 M NaOH solution, what is the concentration of NaCl in the resulting solution? (Assume complete neutralization) —
0.05 M
2.
If 0.5 moles of NaCl are dissolved in enough water to make 2 liters of solution, what is the molarity? —
0.25 M
3.
If 8 grams of oxygen (O₂) react completely, how many moles of oxygen atoms are involved? (Atomic mass of O = 16 g/mol) —
1 mole
4.
In the reaction 2Al + 3Cl₂ → 2AlCl₃, if 1 mole of Al reacts with 1.5 moles of Cl₂, how many moles of AlCl₃ are formed? —
1 mole
5.
If 1 mole of methane (CH₄) burns completely in excess oxygen, how many moles of carbon dioxide (CO₂) are produced? (CH₄ + 2O₂ → CO₂ + 2H₂O) —
1 mole
6.
If 2 moles of hydrogen gas (H₂) react with 1 mole of oxygen gas (O₂) to form water (H₂O), how many moles of water are produced? —
2 moles
7.
In the reaction 2H₂O₂ → 2H₂O + O₂, if 4 moles of H₂O₂ decompose, how many moles of O₂ are produced? —
2 moles
8.
In the reaction 2SO₂ + O₂ → 2SO₃, if 4 moles of SO₂ react, how many moles of O₂ are required? —
2 moles
9.
How many moles are in 18.066 x 10²³ molecules of a substance? —
3 moles
10.
In the reaction 2Na + Cl₂ → 2NaCl, what is the mole ratio of sodium (Na) to chlorine (Cl₂)? —
2:1
11.
What is the atomic mass unit (amu) defined as? —
1/12th the mass of a carbon-12 atom.
12.
What is the percentage composition of oxygen in water (H₂O)? (Atomic masses: H = 1 g/mol, O = 16 g/mol) —
88.9%
13.
What is the molar mass of glucose (C₆H₁₂O₆)? (Atomic masses: C = 12 g/mol, H = 1 g/mol, O = 16 g/mol) —
180 g/mol
14.
In the reaction C + O₂ → CO₂, if 12 g of carbon reacts completely with oxygen, how many grams of CO₂ are produced? (Atomic masses: C = 12 g/mol, O = 16 g/mol) —
44 g
15.
What is the molar mass of water (H₂O)? (Atomic masses: H = 1 g/mol, O = 16 g/mol) —
18 g/mol
16.
What is the mass of 2 moles of Helium (He) gas? (Atomic mass of He = 4 g/mol) —
8 g
17.
In the reaction N₂ + 3H₂ → 2NH₃, if 2 moles of N₂ react with 6 moles of H₂, how many moles of NH₃ are produced? —
4 moles
18.
What is the mole ratio of products to reactants in the reaction 2H₂ + O₂ → 2H₂O? —
2:3
19.
What is the volume occupied by 1 mole of any ideal gas at Standard Temperature and Pressure (STP)? —
22.4 Liters
20.
What is the mass percentage of carbon in methane (CH₄)? (Atomic masses: C = 12 g/mol, H = 1 g/mol) —
21.
What is the mass of 1 mole of electrons, given the mass of an electron is 9.109 x 10⁻³¹ kg? —
5.486 x 10⁻⁷ kg
22.
If 10 grams of calcium carbonate (CaCO₃) are decomposed, producing calcium oxide (CaO) and carbon dioxide (CO₂), what is the maximum theoretical mass of CaO that can be produced? (Molar masses: CaCO₃ = 100 g/mol, CaO = 56 g/mol). CaCO₃ → CaO + CO₂ —
5.6 g
23.
What is the mass of 3 moles of sodium chloride (NaCl)? (Atomic masses: Na = 23 g/mol, Cl = 35.5 g/mol) —
175.5 g
24.
What is Avogadro's number? —
6.022 x 10²³
25.
What is the molar mass of sulfuric acid (H₂SO₄)? (Atomic masses: H = 1 g/mol, S = 32 g/mol, O = 16 g/mol) —
98 g/mol
26.
If a reaction has a theoretical yield of 50 g and an actual yield of 40 g, what is the percentage yield? —
80%
27.
In the reaction A + 2B → C, if 4 moles of A react with 6 moles of B, which is the limiting reactant? —
B
28.
What does the symbol '(aq)' in a chemical equation represent? —
Aqueous solution
29.
If the empirical formula of a compound is CH₂ and its molar mass is 28 g/mol, what is its molecular formula? (Molar mass of CH₂ = 14 g/mol) —
C₂H₄
30.
What is the molecular formula of a compound if its empirical formula is CH₂O and its molar mass is 180 g/mol? (Molar mass of CH₂O = 30 g/mol) —
C₆H₁₂O₆
31.
What does the symbol 'g' in a chemical equation typically represent? —
Gas
32.
Which of the following represents a balanced chemical equation? —
2H₂ + O₂ → 2H₂O
33.
What does it mean for a reactant to be the 'limiting reactant'? —
It is the reactant that is completely consumed first and determines the amount of product formed.
34.
What is the mole concept used to relate? —
Mass and number of particles.
35.
What is the term for the number of moles of solute per kilogram of solvent? —
Molality
36.
What is the mole fraction of a component in a solution? —
Moles of component / Total moles of solution
37.
What is the molarity of a solution? —
Moles of solute per liter of solution.
38.
What does the arrow (→) in a chemical equation signify? —
Yields or produces
39.
What is the empirical formula of a compound? —
The simplest whole-number ratio of atoms of each element in a compound.
40.
What is the definition of a mole? —
The amount of substance containing as many elementary entities as there are atoms in 0.012 kg of carbon-12.
41.
What is the relationship between empirical formula and molecular formula? —
The molecular formula is always a whole-number multiple of the empirical formula.
42.
What is stoichiometry primarily concerned with? —
The quantitative relationships between reactants and products in a chemical reaction.
43.
What is the percentage yield of a reaction? —
The ratio of the actual yield to the theoretical yield, multiplied by 100.
44.
What information can be directly obtained from a balanced chemical equation? —
The mole ratios between reactants and products.
45.
What is the law of conservation of mass, as applied to chemical reactions? —
The total mass of reactants is always equal to the total mass of products.
46.
What is the term for the amount of product actually obtained in a chemical reaction? —
Actual yield
47.
What is the term for the calculation of the relative amounts of substances in a chemical reaction? —
Stoichiometry
48.
What is the process of determining the amount of a substance in a sample using a chemical reaction with a reagent of known concentration called? —
Titration
49.
What is the purpose of balancing chemical equations? —
To ensure the law of conservation of mass is obeyed.
50.
What is the principle behind calculating the theoretical yield of a reaction? —
Using the stoichiometry of the balanced equation and the amount of limiting reactant.