Question

1. 40 g of calcium reacts with 71 g of chlorine to produce ____ g of calcium chloride
2. ____ g of potassium reacts with 16 g of oxygen to produce 94 g of potassium oxide
3. 14 g of lithium reaction with ____ g sulfur to produce 46 g of lithium sulfide
4. 24 g of magnesium reacts with 38 g of fluorine to produce ____ g magnesium fluoride
5. 65.5 g copper reacts with ____ g oxygen to produce 81 g copper (i) oxide
6. 88 g of strontium reacts with 160 g bromine to produce ____ g strontium bromide
7. 46 g of sodium reacts with ____ g chlorine to produce 117 g sodium chloride
8. ____ g iron reacts with 71 g chlorine to produce 129 g of iron (iii) chloride
9. 137 g of barium reacts with ____ g iodine to produce 391 g barium iodide
10. ____ g hydrogen reacts with 32 g of oxygen to produce 34 g of hydrogen peroxide

Explanation:

Step1: Apply law of conservation of mass

The law of conservation of mass states that the total mass of reactants equals the total mass of products in a chemical reaction. So, mass of product = mass of first - reactant+mass of second - reactant, and mass of a reactant=mass of product - mass of the other reactant.

1. Mass of calcium chloride = mass of calcium+mass of chlorine = 40 + 71=111 g

Step2: Find mass of potassium

Mass of potassium = mass of potassium oxide - mass of oxygen = 94 - 16 = 78 g

Step3: Find mass of sulfur

Mass of sulfur = mass of lithium sulfide - mass of lithium = 46 - 14 = 32 g

Step4: Find mass of magnesium fluoride

Mass of magnesium fluoride = mass of magnesium+mass of fluorine = 24 + 38 = 62 g

Step5: Find mass of oxygen

Mass of oxygen = mass of copper (I) oxide - mass of copper = 81 - 65.5 = 15.5 g

Step6: Find mass of strontium bromide

Mass of strontium bromide = mass of strontium+mass of bromine = 88+160 = 248 g

Step7: Find mass of chlorine

Mass of chlorine = mass of sodium chloride - mass of sodium = 117 - 46 = 71 g

Step8: Find mass of iron

Mass of iron = mass of iron (III) chloride - mass of chlorine = 129 - 71 = 58 g

Step9: Find mass of iodine

Mass of iodine = mass of barium iodide - mass of barium = 391 - 137 = 254 g

Step10: Find mass of hydrogen

Mass of hydrogen = mass of hydrogen peroxide - mass of oxygen = 34 - 32 = 2 g

Answer:

1. 111
2. 78
3. 32
4. 62
5. 15.5
6. 248
7. 71
8. 58
9. 254
10. 2