Stoichiometry: from grams of one substance to grams of another

Answer Key - Grade 10 Science Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. 1.

   Respiration gives 6 mol of CO₂ for each mole of glucose. Glucose is 180.18 g/mol and CO₂ 44.01 g/mol. How many grams of CO₂ come from 36.036 g of glucose, to 0.01 g, Esme?

   52.81 g
2. 2.

   Respiration gives 6 mol of water for each mole of glucose. Glucose is 180.18 g/mol and water 18.02 g/mol. How many grams of water come from 54.054 g of glucose, to 0.01 g, Jun?

   32.44 g
3. 3.

   In 2H₂ + O₂ → 2H₂O (equation only), 2 mol of water form per mole of O₂ (32 g/mol); water is 18.02 g/mol. How many grams of water come from 48 g of O₂, Kira?

   54.06 g
4. 4.

   Esme says 180.18 g of glucose must make 180.18 g of CO₂, since mass is conserved. Which reply fits, Luz?

   • Disagree: the total of all reactants equals the total of all products
   • Agree: each product has the reactant's mass
   • Agree: grams carry straight across an equation
5. 5.

   Milo says a 1 : 1 equation means equal grams of each substance. Which reply fits, Milo?

   • Agree: 1 : 1 means 1 g to 1 g
   • Agree, if the substances are solids
   • Disagree: equal moles, but the molar masses differ
6. 6.

   Noah says respiration destroys some of the glucose's mass. Which reply fits, Noah?

   • Disagree: its atoms end up in the CO₂ and water
   • Agree: the mass is used up as energy
   • Agree: the products weigh less than the reactants
7. 7.

   Baking soda (84.01 g/mol) gives CO₂ (44.01 g/mol) 1 : 1 with vinegar. How much CO₂ comes from 21.00 g of baking soda, Pia?

   • 21.00 g, the same mass
   • About 11.00 g
   • About 40.09 g, using the molar masses the wrong way round
8. 8.

   How much baking soda (84.01 g/mol) makes 4.40 g of CO₂ (44.01 g/mol) with vinegar, 1 : 1, Ren?

   • 4.40 g, the same mass
   • About 2.31 g, using the molar masses the wrong way round
   • About 8.40 g
9. 9.

   In respiration, 27.027 g of glucose reacts. How many grams of CO₂ and of water form, Zee?

   • 6.60 g of CO₂ and 2.70 g of water
   • 39.61 g of CO₂ and 16.22 g of water
   • 27.03 g of each, the glucose's mass
10. 10.

    Photosynthesis makes 90.09 g of glucose. How many grams of O₂ are released, Bo?

    • 96.00 g, from 3 mol of O₂
    • 90.09 g, the same mass as the glucose
    • 16.00 g, from 0.5 mol of O₂