Some Basic Concepts Of Chemistry Question 122
Question: What is the atomic weight of an element X for which a sample containing $ 1.58\times 10^{22} $ atoms weigh 1.05 g?
Options:
A) 28 g
B) 20 g
C) 40 g
D) 23 g
Show Answer
Answer:
Correct Answer: C
Solution:
[c] We know that, one mole of an element $ =6.02\times 10^{23} $ atoms = Atomic weight of the element Now, $ 1.58\times 10^{22} $ atoms weigh 1.05 g
$ \therefore $ $ 6.02\times 10^{23} $ atoms weigh
$ =\frac{(1.05\times 6.02\times 10^{23})}{1.58\times 10^{22}} $
= 40 g
Atomic weight of $ X=40g $
