Answer: The empirical formula for the given compound is 
Explanation : Given,
Percentage of C = 38.8 %
Percentage of H = 16.2 %
Percentage of N = 45.1 %
Let the mass of compound be 100 g. So, percentages given are taken as mass.
Mass of C = 38.8 g
Mass of H = 16.2 g
Mass of N = 45.4 g
To formulate the empirical formula, we need to follow some steps:
Step 1: Converting the given masses into moles.
Moles of Carbon =
Moles of Hydrogen = 
Moles of Nitrogen = 
Step 2: Calculating the mole ratio of the given elements.
For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 3.23 moles.
For Carbon = 
For Hydrogen = 
For Oxygen = 
Step 3: Taking the mole ratio as their subscripts.
The ratio of C : H : N = 1 : 5 : 1
Hence, the empirical formula for the given compound is 
<u>Answer: </u>The volume of the solution is 85.7 mL
<u>Explanation:</u>
Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:
.....(1)
We are given:
Molarity of solution = 0.600 M
Given mass of
= 12.00 g
We know, molar mass of ![BaSO_4=[(1\times 137.33)+(1\times 32.07)+(4\times 16)]=233.4g/mol](https://tex.z-dn.net/?f=BaSO_4%3D%5B%281%5Ctimes%20137.33%29%2B%281%5Ctimes%2032.07%29%2B%284%5Ctimes%2016%29%5D%3D233.4g%2Fmol)
Putting values in equation 1, we get:

The rule of significant number that is applied for the problems having multiplication and division:
The least number of significant figures in any number of the problem determines the number of significant figures in the answer.
Here, the least number of significant figures is 3 that is determined by the number, 0.600. Thus, the answer must have these many significant figures only.
Hence, the volume of the solution is 85.7 mL
The density of CO2 getting from experiment is 0.1/0.056 = 1.79 g/L. The percent error of this is (1.96 -1.79)/1.96*100%=8.67%. So the approximate percent error is 8.67%.