How many moles are there in 3.0 g of \(O_2\)? [O = 16.0]

Chemistry

WAEC 2023

A. 0.0093 moles.
B. 0.0930 moles.
C. 0.0625 moles.
D. 0.6250 moles.

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Correct Answer: Option B

Explanation

Number of moles = Mass / Molar mass
Given that the molar mass of oxygen \(O_2\) is 32.0 g/mol (2 × 16.0 g/mol), you can calculate the number of moles:
Number of moles = 3.0 g / 32.0 g/mol = 0.09375 moles
Rounded to four significant figures, the number of moles in 3.0 g of O2 is approximately 0.0938 moles.
Therefore, the closest answer choice is:
0.0930 moles.

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