Answer:
The empirical formula of compound is C₂H₆O.
Explanation:
Given data:
Mass of carbon = 12 g
Mass of hydrogen = 3 g
Mass of oxygen = 8 g
Empirical formula of compound = ?
Solution:
First of all we will calculate the gram atom of each elements.
no of gram atom of carbon = 12 g / 12 g/mol = 1 g atoms
no of gram atom of hydrogen = 3 g / 1 g/mol = 3 g atoms
no of gram atom of oxygen = 8 g / 16 g/mol = 0.5 g atoms
Now we will calculate the atomic ratio by dividing the gram atoms with the 0.5 because it is the smallest number among these three.
C:H:O = 1/0.5 : 3/0.5 : 0.5/0.5
C:H:O = 2 : 6 : 1
The empirical formula of compound will be C₂H₆O
Answer:
Molar concentration of the weak acid solution is 0.0932
Explanation:
Using the formula: 
Where Ca = molarity of acid
Cb = molarity of base = 0.0981 M
Va = volume of acid = 25.0 mL
Vb = volume of base = 23.74 mL
na = mole of acid
nb = mole of base
Since the acid is monopromatic, 1 mole of the acid will require 1 mole of NaOH. Hence, na = nb = 1
Therefore, 
Ca = 0.0981 x 23.74/25.0
= 0.093155 M
To 4 significant figure = 0.0932 M
Mass percentage is another way of expressing concentration of a substance in a mixture. Mass percentage is calculated as the mass of a component divided by the total mass of the mixture, multiplied by 100%. It is calculated as follows:
% CaCO3 = (<span>1.82g of calcium carbonate</span> / (1.05 g SiO2 + 0.69 g of cellulose + <span>1.82g of calcium carbonate)) x 100% = 51.12% Calcium carbonate</span>
2. Precipitation, because when it rains the water that was taken when it was evaporated is replaced and it fills the lake back up
