Percent Composition

Front

What is percent composition?

Back

Percent composition is the percentage by mass of each element in a compound, calculated by dividing the mass of each element by the total mass of the compound and multiplying by 100.

Front

How do you calculate the percent composition of an element in a compound?

Back

To calculate percent composition, use the formula: (mass of element in 1 mole of compound / molar mass of compound) x 100.

Front

What is the percent composition of oxygen in carbon monoxide (CO)?

Back

57%.

Front

What is the percent composition of carbon in carbon monoxide (CO)?

Back

43%.

Front

What is the percent composition of magnesium in magnesium bromide (MgBr2)?

Back

13%.

Front

What is the percent composition of bromine in magnesium bromide (MgBr2)?

Back

87%.

Front

If a compound has a molar mass of 100 g/mol and contains 20 g of element A, what is the percent composition of element A?

Back

20%.

Front

Why is it important to consider the number of atoms when calculating percent composition?

Back

The number of atoms affects the total mass contributed by each element, which is crucial for accurate percent composition calculations.

Front

What is the total atomic mass of carbon monoxide (CO)?

Back

The total atomic mass of CO is approximately 28 g/mol (12 g/mol for carbon and 16 g/mol for oxygen).

Front

What is the total atomic mass of magnesium bromide (MgBr2)?

Back

The total atomic mass of MgBr2 is approximately 200 g/mol (24 g/mol for magnesium and 2 x 80 g/mol for bromine).