Question

Calculate the mass in grams of benzophenone required to make a solution of 2.5 mmoles

Answer 1

Answer:

0.46 grams (C₆H₅)₂CO

Explanation:

To find the mass of benzophenone ((C₆H₅)₂CO), you need to (1) convert mmoles to moles and then (2) convert moles to grams (via molar mass). It is important to arrange the conversions/ratios in a way that allows for the cancellation of units. The final answer should have 2 sig figs to match the sig figs of the given value (2.5 mmoles).

Molar Mass ((C₆H₅)₂CO): 13(12.011 g/mol) + 10(1.008 g/mol) + 15.998 g/mol

Molar Mass ((C₆H₅)₂CO): 182.221 g/mol

2.5 mmoles (C₆H₅)₂CO               1 mole                  182.221 g
-----------------------------------  x  ------------------------  x  -------------------  =
                                                1,000 mmoles            1 mole

=  0.46 grams (C₆H₅)₂CO