Isiin semua dong gan , lagi pusing nih

1)
a. 4(12) + 2(16) + 1(1) = 81
b. 2(12)+2(1) + 2(16) = 58
c. 6(12) + 12(1) +6(16) = 180

2)
a. n = (2.10^20) / (6,02 x 10^23) = 3,3 x10-4 mol
b. n = 1,24 x10^23 / 6,02 x 10^23 = 0,21 mol
c. n = 3,24 x 10^19 / (6,02 x 10^23) = 0,52 x 10-4

3)
a. x = 0,76 x 6,02 x 10^23 = 4,58 x 10^23 partikel
b. x = 0,12 x 6,02 x 10^23 = 0,72 x 10^23
c. x = 1,3 x 6,02 x 10^23 = 7,83 x 10^23

4)
a) 12 gram H2 = 12/2 = 6 mol
b) 33 gram O2 = 33/32 =1,03 mol

5)
a) Ar X = g/n = 10 / 0,5 = 20
b) Ar Y = g/n = 12 /0,3 = 40