Question

What is the percentage composition for H2O in this compound Al(OH)3.2H2O?

a
50.55%
b
40.05%
c
32.73 %
d
65.09%

Answer 1

32.73%

Step-by-step explanation:

To solve this problem, first find the molar mass of Al(OH)₃.2H₂O

Atomic mass of Al = 27g/mol

O = 16g/mol

H = 1g/mol

Molar mass = 27 + 3(16 + 1) + 2(2(1) + 16)

= 27 + 51 + 36

= 114g/mol

Percentage composition =
`(36)/(114)` x 100 = 32.73%