Answer:
0.89 g 
Step-by-step explanation:
We are given;
- 4.82 mmol of Diphenylmethanol 
 
We are required to convert moles to mass in grams 
- We need to know the relationship between mass, moles and molar mass
 
- Therefore, when we have molar mass and moles of a compound;
 

In this case;
- We need to know the molar mass of diphenylmethanol 
 - Molar mass of C₁₃H₁₂O = 184.234 g/mol 
 
But, 1 mol = 1000 mmol
Thus, 4.82 mmol = 0.00482 moles
Mass of C₁₃H₁₂O = 0.00482 moles × 184.234 g/mol 
 = 0.888 g 
 = 0.89 g 
Thus, the mass of C₁₃H₁₂O in 4.82 mmol is 0.89 g