Answer:
3 moles of Oxygen
Explanation:
The chemical formula of a compound is a representation which shows all the elements therein and the mole relationship between them expressed as subscripts.
NaHCO₃ implies:
1 mole of baking soda contains:
1 mole of Na
1 mole of Hydrogen
1 mole of carbon
And 3 moles of Oxygen
In a chemical equation the coefficients represent the ration of the number of moles. therefore, if you have 16 moles of oxygen, you would have 32 moles of water.
Answer : The correct option is, (B) 
Solution :
According to the Graham's law, the rate of effusion of gas is inversely proportional to the square root of the molar mass of gas.
or,
..........(1)
where,
= rate of effusion of unknown gas = 
= rate of effusion of oxygen gas = 
= molar mass of unknown gas = ?
= molar mass of oxygen gas = 32 g/mole
Now put all the given values in the above formula 1, we get:
The unknown gas could be carbon dioxide 
that has approximately 44 g/mole of molar mass.
Thus, the unknown gas could be carbon dioxide
A control group is the group in an experiment that does not receive any sort of change, to then be compared to the other treated objects at the end of the study.
