Chemistry
The atomic masses of sulphur (S), oxygen (O), and helium (He) are approximately 32, 16, and 4 respectively.
Which of the following statements regarding the number of atoms in 32 g of sulphur, 16 g of oxygen, and 4 g of helium is correct?
P. 16 g of oxygen contains four times the number of atoms as 4 g of helium.
Q. 16 g of oxygen contains half the number of atoms as 32 g of sulphur.
- only P
- only Q
- both P and Q
- neither P nor Q
Mole Concept
ICSE Sp 2024
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Answer
neither P nor Q
Reason —
Number of atoms = x NA
where NA is the Avogadro's number = 6.023 x 1023
Number of atoms in 32 g of sulphur (s) = x NA = NA
Number of atoms in 16 g of oxygen (O) = x NA = NA
Number of atoms in 4 g of helium (He) = x NA = NA
Hence, all have same number of atoms which is = 6.023 x 1023
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