# Percent by mass calculation

6. Assume that coal can be represented by the formula C135H96O9NS

What is the percent of nitrogen by mass in this coal?

If three tons of coal were burned completely, what mass of nitrogen in NO would be produced.

Please show calculations.

7. This unbalanced equation represents the las step in the production of pure silicon for use in solar cells.

Mg (s) + _ SiCl4 (l) ---->_ MgCl2 (l) + _ Si (s)

How many electrons are transferred per atom of pure silicon formed?

b. Is the production of pure silicon on oxidation or a reduction reaction. Why do you think so.

https://brainmass.com/chemistry/physical-chemistry/percent-mass-calculation-110384

#### Solution Preview

6a) What is the percent of nitrogen by mass in this coal

I. Look up the atomic masses for each of the elements in the formula:-

C - 12.01 H - 1.01 O - 16.00 N - 14.01 S - 32.06

II. Determine how many grams of each element are present in one mole of C135H96O9NS:-

C - 135 moles x 12.01 g/mole = 1621.35 g

H - 96 moles x 1.01 ...

#### Solution Summary

The percent by mass calculations are determined.