The number of moles of O2 in 2.24 L of O2 gas.

calculate at STP

The number of moles of  is required.

The number of moles of is 0.2 moles.

V = Volume = 2.24 L

= Density of at STP = 1.429 g/L

M = Molar mass of = 16 g/mol

Density is given by

Molar mass is given by

The number of moles of is 0.2 moles.

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0.1 mol O2

Explanation:

1 mol of any gas at STP = 22.4 L

2.24L/22.4L = 0.1

1mol * 0.1 = 0.1 mol

you have 0.1 mol of O2

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.

it's c. elements are placed in rows based on how may valencies electrons have.