1. Hitunglah massa dari: a. 5 mol besi (Ar Fe = 56 ) b. 0,75 mol urea CO(NH2)2 (Ar C = 12, O = 16, dan H = 1 )

Question

Kimia Diposting : 2017-03-25 Diupdate : 2021-05-03 riyansyahdwi

Pertanyaan

1. Hitunglah massa dari:
a. 5 mol besi (Ar Fe = 56 )
b. 0,75 mol urea CO(NH2)2 (Ar C = 12, O = 16, dan H = 1 )

Answer 1

a) n = m/Ar
5 = m/56
280 = m
m = 280 gr
b) n = m/Mr
¾ = m/(12+16+2•14+4•1)
¾ = m/60
¾ × 60 = m
45 = m
m = 45 gr