Answer:
0.53
Step-by-step explanation:
A solution is made by mixing 42 g of chloroform (CHCl₃) and 31 g of heptane (C₇H₁₆). Calculate the mole fraction of chloroform in this solution. Be sure your answer has the correct number of significant digits.
Step 1: Calculate the number of moles of chloroform
The molar mass of CHCl₃ is 119.38 g/mol.
42 g × 1 mol/119.38 g = 0.35 mol
Step 2: Calculate the number of moles of heptane
The molar mass of C₇H₁₆ is 100.20 g/mol.
31 g × 1 mol/100.20 g = 0.31 mol
Step 3: Calculate the total number of moles
We will use the following expression.
n = nCHCl₃ + nC₇H₁₆ = 0.35 mol + 0.31 mol = 0.66 mol
Step 4: Calculate the mole fraction of chloroform
We will use the following expression.
χ(CHCl₃) = nCHCl₃ / n
χ(CHCl₃) = 0.35 mol / 0.66 mol = 0.53