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3 years ago

HELP

Chemistry

1 answer:

Wittaler [7]3 years ago

8 0

Answer:

Explanation:

Given parameters:

Number of moles of CaO = 0.22moles

Unknown:

Mass of CaO = ?

Solution:

Mass, number of moles and molar mass are related using the expression below;

Mass = number of moles x molar mass

Molar mass of CaO = 40 + 16 = 56g/mol

Insert the parameters and solve;

Mass = 0.22 x 56 = 12.32g

Given parameters:

Number of moles of NaCl = 0.83moles

Unknown:

mass of NaCl = ?

Solution:

Also,

Mass = number of moles x molar mass

Molar mass of NaCl = 23 + 35.5 = 58.5g/mol

Now insert the parameters and solve;

mass = 0.83 x 58.5

mass = 48.6g

Given parameters:

Number of moles of H₂SO₄ = 0.5moles

Unknown:

mass of H₂SO₄ = ?

Solution:

Mass = number of moles x molar mass

Molar mass of H₂SO₄ = 2(1) + 32 + 4(16) = 98g/mol

Insert the parameters and solve;

Mass = 0.5 x 98 = 49g

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Yo sup??

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