Question

Whats is the percentage composition of KOH

Answer 1

Mass of whole KOH = mass of 1K + mass of 1O + mass of 1H  

= 39.10 + 16.00 + 1.01  

= 56.11g  

%Comp of Potassium = mass of K / mass of KOH  

= 39.10 / 56.11 = 69.7%  

%Comp of Oxygen = mass of O / mass of KOH  

= 16.00 / 56.11 = 28.5%  

%Comp of Hydrogen = mass of H / mass of KOH  

= 1.01 / 56.11 = 1.8%

Answer 2

SoluTion:

Given compound :

• KOH ( potassium hydroxide )

We've to find its percentage composition. Firstly we've to find its Molecular mass.

Known quantities :

• Atomic mass of potassium = 39 g
• Atomic mass of oxygen = 16
• atomic mass of Hydrogen = 1

molecular mass = 39 + 16 + 1

→ Molecular mass of Potassium hydroxide is 56 g

$\rule{200}2$

Percentage composition of potassium :

→ 69.687%

Percentage composition of oxygen :

→ 28.517%

Percentage composition of hydrogen :

→ 1.797%