krit.club logo

Stoichiometry

Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.

Relative atomic mass and relative molecular mass

Subtopic

Relative atomic mass and relative molecular mass under Stoichiometry for Grade 11 IGCSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    The following diagram represents how different isotopes contribute to the calculation of the relative atomic mass of an element. If Isotope 1 has a mass of 10 and Isotope 2 has a mass of 11, and they are present in equal amounts, what is the ArA_r?

    A.

    10.0

    B.

    11.0

    C.

    21.0

    D.

    10.5

  2. 2.

    Which of the following statements about relative molecular mass is true?

    A.

    It is a dimensionless quantity and has no units.

    B.

    It is measured in grams per mole (g/molg/mol) only.

    C.

    It is always a whole number for every molecule.

    D.

    It represents the mass of 6.02×10236.02 \times 10^{23} atoms.

  3. 3.

    Calculate the relative molecular mass (MrM_r) of carbon dioxide (CO2CO_2). (Given ArA_r: C=12,O=16C=12, O=16)

    A.

    28

    B.

    32

    C.

    44

    D.

    56

Download the worksheet for Stoichiometry - Relative atomic mass and relative molecular mass to practice offline. It includes additional chapter-level practice questions.

The mole concept

Subtopic

The mole concept under Stoichiometry for Grade 11 IGCSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    According to the mole concept, one mole of any substance contains how many representative particles?

    A.

    1.20×10241.20 \times 10^{24}

    B.

    6.02×10236.02 \times 10^{23}

    C.

    3.01×10233.01 \times 10^{23}

    D.

    6.02×10226.02 \times 10^{22}

  2. 2.

    How many moles are present in 22g of carbon dioxide, CO2CO_2? (MrM_r of CO2=44CO_2 = 44)

    A.

    2.0 mol

    B.

    1.0 mol

    C.

    0.25 mol

    D.

    0.5 mol

  3. 3.

    What is the volume occupied by 2.0 moles of oxygen gas (O2O_2) at room temperature and pressure (r.t.p.)?

    A.

    48 dm3dm^3

    B.

    24 dm3dm^3

    C.

    12 dm3dm^3

    D.

    96 dm3dm^3

Download the worksheet for Stoichiometry - The mole concept to practice offline. It includes additional chapter-level practice questions.

Empirical and molecular formulae

Subtopic

Empirical and molecular formulae under Stoichiometry for Grade 11 IGCSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    The empirical formula of a compound is CH2CH_2. If its relative molecular mass (MrM_r) is 42, what is its molecular formula? (Relative atomic masses: C=12,H=1C=12, H=1)

    A.

    CH2CH_2

    B.

    C2H4C_2H_4

    C.

    C4H8C_4H_8

    D.

    C3H6C_3H_6

  2. 2.

    Which pair of compounds has the same empirical formula?

    A.

    CH4CH_4 and C2H6C_2H_6

    B.

    C2H2C_2H_2 and C6H6C_6H_6

    C.

    NO2NO_2 and N2ON_2O

    D.

    C3H8C_3H_8 and C4H10C_4H_{10}

  3. 3.

    A compound has the molecular formula C6H12O6C_6H_{12}O_6. What is its empirical formula?

    A.

    C3H6O3C_3H_6O_3

    B.

    CH2OCH_2O

    C.

    C2H4O2C_2H_4O_2

    D.

    CH3OCH_3O

Download the worksheet for Stoichiometry - Empirical and molecular formulae to practice offline. It includes additional chapter-level practice questions.

Reacting masses and volumes

Subtopic

Reacting masses and volumes under Stoichiometry for Grade 11 IGCSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    In a chemical reaction, the theoretical yield of copper is calculated to be 10.0 g10.0\ g. However, after performing the experiment, a student collects 8.5 g8.5\ g of copper. What is the percentage yield?

    A.

    15%

    B.

    117%

    C.

    8.5%

    D.

    85%

  2. 2.

    A hydrocarbon compound is found to contain 80% carbon and 20% hydrogen by mass. What is the empirical formula of this compound? (Ar:C=12,H=1A_r: C=12, H=1)

    A.

    CHCH

    B.

    CH2CH_2

    C.

    CH3CH_3

    D.

    C2H2C_2H_2

  3. 3.

    Calculate the volume occupied by 0.5 mol0.5\ mol of carbon dioxide (CO2CO_2) gas at room temperature and pressure (RTP). (Molar volume at RTP = 24 dm3/mol24\ dm^3/mol)

    A.

    12 dm312\ dm^3

    B.

    24 dm324\ dm^3

    C.

    48 dm348\ dm^3

    D.

    6 dm36\ dm^3

Download the worksheet for Stoichiometry - Reacting masses and volumes to practice offline. It includes additional chapter-level practice questions.

Concentration and titrations

Subtopic

Concentration and titrations under Stoichiometry for Grade 11 IGCSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    How many moles of solute are present in 2.0 dm32.0\ dm^3 of a solution with a concentration of 0.5 mol/dm30.5\ mol/dm^3?

    A.

    0.25 mol0.25\ mol

    B.

    4.0 mol4.0\ mol

    C.

    2.5 mol2.5\ mol

    D.

    1.0 mol1.0\ mol

  2. 2.

    A student needs to convert a volume from cubic centimeters (cm3cm^3) to cubic decimeters (dm3dm^3) for a stoichiometry calculation. What is the correct conversion for 450 cm3450\ cm^3?

    A.

    0.45 dm30.45\ dm^3

    B.

    4.5 dm34.5\ dm^3

    C.

    45 dm345\ dm^3

    D.

    0.045 dm30.045\ dm^3

  3. 3.

    In a laboratory titration, which piece of glassware is most appropriate for accurately measuring and transferring exactly 25.0 cm325.0\ cm^3 of a reactant solution into a conical flask?

    A.

    Beaker

    B.

    Measuring cylinder

    C.

    Volumetric pipette

    D.

    Burette

Download the worksheet for Stoichiometry - Concentration and titrations to practice offline. It includes additional chapter-level practice questions.

Stoichiometry - IGCSE Grade 11 Chemistry Notes & Revision | Krit.club