Question

1. Вычислите массовую долю кальция в следующих соединениях: а) СаCl2 ; б) СаSO4 ; в) Са3(PO4)2;

Answer 1

Ответ:

a) СаCl2 что бы найти массовую долю нужно Ar элемента поделить на Mr элемента Ar(Ca2)=80

Mr вещества равно 151 80/151 равно 0,529(52,9%)

Объяснение:

и по этому принципу делать всё

Answer 2

Calculating the Mass Fraction of Calcium in Compounds

To calculate the mass fraction of calcium in the given compounds, we can use the following information:

a) CaCl2: The molar mass of CaCl2 is 110.98 g/mol. The molar mass of calcium (Ca) is 40.08 g/mol.

The mass fraction of calcium in CaCl2 can be calculated using the formula: \[ \text{Mass fraction of Ca in CaCl2} = \frac{\text{Molar mass of Ca}}{\text{Molar mass of CaCl2}} \times 100\% \]

Substituting the values: \[ \text{Mass fraction of Ca in CaCl2} = \frac{40.08}{110.98} \times 100\% = 36.12\% \]

b) CaSO4: The molar mass of CaSO4 is 136.14 g/mol.

The mass fraction of calcium in CaSO4 can be calculated using the same formula: \[ \text{Mass fraction of Ca in CaSO4} = \frac{40.08}{136.14} \times 100\% = 29.44\% \]

c) Ca3(PO4)2: The molar mass of Ca3(PO4)2 is 310.18 g/mol.

The mass fraction of calcium in Ca3(PO4)2 can be calculated using the same formula: \[ \text{Mass fraction of Ca in Ca3(PO4)2} = \frac{3 \times 40.08}{310.18} \times 100\% = 38.89\% \]

So, the mass fractions of calcium in the given compounds are: - a) CaCl2: 36.12% - b) CaSO4: 29.44% - c) Ca3(PO4)2: 38.89%