Question

Oxygen forms a number of compounds with nitrogen, many of which are quite reactive. one such compound is 36.86 % by mass n . calculate the number of grams of oxygen present in a sample of this compound that contains 56.00 grams of n .

Answer 1

Mass percentage is defined as the ratio of mass of the element to the total mass of the compound.

The formula of mass percentage is given by:

Mass percentage =
`(mass  of  the  element)/(total  mass  of  the  compound)* 100` (1)

mass of nitrogen = 56.00 grams

Let x be the total mass of the compound.

Put the given values in formula (1):

`(36.86)/(100) =(56.00 g)/(x)`

x=
`(100)/(36.86)* 56 g`

x= 151.92 g

total mass of the compound = 151.92 g

To calculate the mass of oxygen in grams, subtract the mass of nitrogen from the total mass of the compound.

Mass of oxygen = 151.92 g - 56 .00 g = 95.92 g

Thus, mass of oxygen in grams = 95.92 grams.