14+3=17 , 17 is the rmm for one mole of ammonia, so 17 x 8.96 =152.32

2) 5.66 x 10^23= 5660.
one mole of water is 18gmol-1
using avogadros constant, the mass of one mole of water in kilograms is:
0.00000000000000000000000002991507kg

times this by 5660 which is 2.991507 × 10-26kg x 5660 = 1.693192962 x 10^30

3) 10 grams aluminum (1 mole Al/26.98 grams)(6.022 × 1023/ 1 mole Al)

= 2.2 × 10^23 atoms of aluminum

divide this by 10, which is :
2.2 x 10^22 atoms in one gram

times this by 45.9 which is 1.0098 x 10^24 atoms in 45.9g of aluminium.

hope i helped :)

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