January 2019 NY Regents Chemistry Exam
36 What is the number of moles of CO2 in a 220.-gram sample of CO2 (gram-formula mass = 44 g/mol)?
(1) 0.20 mol
(2) 5.0 mol (3) 15 mol
(4) 44 mol
Solution: Table T on the Reference Table shows the formula for mole calculations. number of moles = given mass/ gram-formula mass.
Number of moles. = 220g/44g/mol = 5.0moles
Answer: 2
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