Question

urea, chemical formula (NH2)2co is used for fertilizer and many other things. calculate the number of N,C,O and H atoms in 1.58×10^4g of urea .

Answer 1

(NH2)2CO = 60 g/mol

60 g urea contain 2 x 6.023 x 10²³ N atoms

1.58 x 10⁴ g urea contain 1.58 x 10⁴ x2 x 6.023 x 10²³ / 60 = 3.17 x 10²⁶ N atoms

number of N atoms =   3.17 x 10²⁶

number of C atoms = N atoms / 2 = 3.17 x 10²⁶ / 2 = 1.585 x 10²⁶ C atoms

number of C atoms = 1.585 x 10²⁶   

number of O atoms = number of C atoms = 1.585 x 10²⁶

number of C atoms = 1.585 x 10²⁶   

numberof H atoms = 2 x N atoms = 2 x 3.17 x 10²⁶ = 6.34 x 10²⁶

number of H atoms = 6.34 x 10²⁶ atoms