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2 years ago

Please help!! i need the answer ASAP!

Chemistry

1 answer:

nirvana33 [79]2 years ago

7 0

Answer:

23.34 %.

Explanation:

The percentage of water must be calculated as a mass percent.

We need to find the mass of water, and the total mass in one mole of the compound. For that we need to use the atomic masses of each element and take in consideration the number of atoms of each element in the formula unit.

Atomic masses of the elements:

Cd: 112.411 g/mol, N: 14.0067 g/mol, O: 15.999 g/mol, and H: 1.008 g/mol.

Mass of the formula unit:

Cd(NO₃)₂•4H₂O

mass of the formula unit = (At. mass of Cd) + 2(At. mass of N) + 10(At. mass of O) + 8(At. mass of H) = (112.411 g/mol) + 2(14.0067 g/mol) + 10(15.999 g/mol) + 8(1.008 g/mol) = 308.5 g/mol.

Mass of water in the formula unit:

mass of water = (4 × 2 × 1.008 g/mol) + (4 × 15.999 g/mol) = 72.0 g/mol.

So, the percent of water in the compound = [mass of water / mass of the formula unit] × 100 = [(72.0 g/mol)/(308.5 g/mol)] × 100 = 23.34 %

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2 years ago

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Answer:

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Explanation:

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2 years ago

A vacuum gage connected to a chamber reads 35 kpa at a location where the atmospheric pressure is 92 kpa. determine the absolute

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Vacuum gage connected to a chamber reads 35 kpa at a location where the atmospheric pressure is 92 kpa then the absolute pressure in the chamber and express is 57kpa

Gauge pressure is the pressure relative to atmospheric pressure. Gauge pressure is positive for pressures above atmospheric pressure, and negative for pressures and absolute pressure is the sum of gauge pressure and atmospheric pressure

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brainly.com/question/28498660

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1 year ago

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2 years ago

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