Question

One mole of oxygen gas at STP is equal to,(this question has multiple correct options):
A. $6.022\times {{10}^{23}}$ molecules of oxygen
B. $6.022\times {{10}^{23}}$atoms of oxygen
C. 16 g of oxygen
D. 32 g of oxygen

Answer 1

Hint : As the options are tricky and it's given that this is a multiple choice based question, we will solve this numerical with the help of two definitions of one mole.
First definition is one mole of any substance is equal to ${{\text{N}}_{\text{A}}}$ (Avogadro)number of particles of that substance.
Second definition is that the weight of one mole of substance is equal to its atomic molecular weight.
Complete step by step solution:
With the help of these two definitions let's see the whole solution.
1 mole of ${{\text{O}}_{\text{2}}}$is equal to ${{\text{N}}_{\text{A}}}$(Avogadro) number of molecules of ${{\text{O}}_{\text{2}}}$ which means it has $6.022\times {{10}^{23}}$ molecules of oxygen
1 mole of oxygen gas at STP has $2\times 6.022\times {{10}^{23}}$ atoms of oxygen
Molecular weight of oxygen is $2\times 16$=32
Therefore, we can conclude that option A and D both are correct.
Additional Information:
STP(Standard Temperature and Pressure) - The standard temperature is equal to 0 degree Celsius or 273.15K. Standard Pressure is 1 Atm, or 101.3kPa or 760 mmHg.

At STP, 1 mole of any gas occupies 22.4L of solution.
Density of gas at STP=molar mass/22.4L
Note: There are high chances of making mistakes in this question as first of all this is a multiple choice question and second thing which is most important to remember while solving these types of questions is to always see whether the given substance is in atom or molecule.