Reacting Masses

avatar
Created by
Ahmed Abubaker

Cards (6)

    • Calculate the mass of magnesium chloride that could be produced from 72g of magnesium. Assume the chlorine is unlimited -- Mg + Cl₂ → MgCl₂ -- ignore chlorine since they say its unlimited
    • Mg -- moles=72/24=3
    • The big numbers before the element means we have 1 mole of that element which means we have 3 moles of magnesium chloride
    • MgCl₂ -- mass= 3 x 95 = 285g
    • Calculate the mass of calcium sulfate that could be produced from 80g of calcium. Assume that the sulfuric acid is unlimited -- Ca + H₂SO₄ → CaSO₄ + H₂
    • Ca -- moles=80/40=2
    • The big numbers before the element means we have 1 mole of that element which means we have 2 moles of calcium sulfate
    • CaSO₄ -- mass= 2 x 136 = 272g
    • Calculate the mass of calcium carbonate that would need to produce 224g of calcium oxide
    • CaO -- moles=224/56=4
    • The big numbers before the element means we have 1 mole of that element which means we have 4 moles of calcium carbonate
    • CaCO₃ -- mass= 4 x 100 = 400g
    • Calculate the mass of magnesium chloride that could be produced from 146g of hydrochloric acid. Assume that the magnesium hydroxide is unlimited -- Mg(OH)₂ + 2HCl → MgCl₂ + H₂O
    • Since there's a 2 before the HCl, we know it has 2 moles and since there's nothing before the MgCl₂, we know it has 1 mole
    • HCl -- moles=146/36.5=4 - the equation tells us that 2 moles of HCl make one mole of MgCl₂, so we have to divide 4 by two so 4 moles of HCl will make 2 moles of MgCl₂
    • MgCl₂ -- mass= 2 x 95 = 190g
    • Calculate the mass of sodium sulfate that could be produced from 240g of sodium hydroxide. Assume that the sulfuric acid is unlimited -- 2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
    • Since there's a 2 before the NaOH, we know it has 2 moles and since there's nothing before the Na₂SO₄, we know it has 1 mole
    • NaOH -- moles=240/40=6 - the equation tells us that 6 moles of NaOH make one mole of Na₂SO₄, so we have to divide 6 by 2 so 6 moles of NaOH will make 3 moles of Na₂SO₄
    • Na₂SO₄ -- mass= 3 x 142 = 426g
    • Calculate the mass of hydrogen peroxide that could produce 64g of oxygen -- 2H₂O₂ → 2H₂O + O₂
    • Since there's a 2 before H₂O₂, we know it has 2 moles and as O₂ has nothing before it, we know it has 1 mole
    • O₂ -- moles=64/32=2 - the equation tells us that 2 moles of 2H₂O₂ make one mole of O₂ so we need 4 moles of 2H₂O₂
    • H₂O₂ -- mass= 4 x 34 = 136g