Answer:
a) 31 g
b) 0.867, 0.132
c) 86.75%, 13.24%
Explanation:
Given:
Mass of the sample of galena = 234 g
Mass of the lead in the sample = 203 g
Now,
galena = sulfur + lead
thus,
a) Mass of the sulfur will be calculated as:
= mass of the sample of galena - mass of lead
on substituting the values, we have
= 234 - 203
or
= 31 g
b) Now,
the mass fraction of lead will be calculated as = ( mass of lead) / (total mass of the galena sample)
= 203/234 = 0.867
and,
Mass fraction of sulfur will be = ( mass of the sulfur in the sample) / ( total mass of the sample)
thus we have
= 31/234
⇒ 0.132
(c) Now the mass percentage of lead in the sample = (mass of lead in the sample ) / (total mass of sample) × 100%
= (203 / 234) x 100%
= 86.75%
and
the mass percentage of sulfur in the sample = ( mass of sulfur in the sample ) / (total mass of the sample) × 100%
= (31 / 234) × 100%
⇒ 13.24%