Solution (K₂O)
Step 1: Calculate the molar mass of K₂O.
molar mass = (39.10 g/mol × 2) + (16.00 g/mol × 1)
molar mass = 94.20 g/mol
Step 2: Calculate the percentage composition of K₂O.
For %K
[tex]\text{\%K} = \frac{\text{39.10 g/mol × 2}}{\text{94.20 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%K = 83.01\%}}[/tex]
For %O
[tex]\text{\%O} = \frac{\text{16.00 g/mol × 1}}{\text{94.20 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%O = 16.99\%}}[/tex]
Solution (Mg(OH)₂)
Step 1: Calculate the molar mass of Mg(OH)₂.
molar mass = (24.31 g/mol × 1) + (16.00 g/mol × 2) + (1.008 g/mol × 2)
molar mass = 58.326 g/mol
Step 2: Calculate the percentage composition of Mg(OH)₂.
For %Mg
[tex]\text{\%Mg} = \frac{\text{24.31 g/mol × 1}}{\text{58.326 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%Mg = 41.68\%}}[/tex]
For %O
[tex]\text{\%O} = \frac{\text{16.00 g/mol × 2}}{\text{58.326 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%O = 54.86\%}}[/tex]
For %H
[tex]\text{\%H} = \frac{\text{1.008 g/mol × 2}}{\text{58.326 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%H = 3.46\%}}[/tex]
Solution (NaHCO₃)
Step 1: Calculate the molar mass of NaHCO₃.
molar mass = (22.99 g/mol × 1) + (1.008 g/mol × 1) + (12.01 g/mol × 1) + (16.00 g/mol × 3)
molar mass = 84.008 g/mol
Step 2: Calculate the percentage composition of NaHCO₃.
For %Na
[tex]\text{\%Na} = \frac{\text{22.99 g/mol × 1}}{\text{84.008 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%Na = 27.3664\%}}[/tex]
For %H
[tex]\text{\%H} = \frac{\text{1.008 g/mol × 1}}{\text{84.008 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%H = 1.1999\%}}[/tex]
For %C
[tex]\text{\%C} = \frac{\text{12.01 g/mol × 1}}{\text{84.008 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%C = 14.2963\%}}[/tex]
For %O
[tex]\text{\%O} = \frac{\text{16.00 g/mol × 3}}{\text{84.008 g/mol}} × 100[/tex]
[tex]\boxed{\text{\%O = 57.1374\%}}[/tex]
#CarryOnLearning
