How many atoms are present in 6.0g of magnesium? [Mg = 24, N.A = 6.02 x 10 \(^{23}\)mol]
- 1.20 x 10\(^{22}\)
- 2.4 x 10\(^{22}\)
-
1.51 x 10\(^{23}\)
- 3.02 x 10\(^{22}\)
The correct answer is: C
Explanation
Using the formula, Number of moles = \(\frac{Number of atoms or molecules}{Avogadro number}\)
Given: Mass of Magnessium = 6g
Mass number of Mg = 24g/mol
Number of moles = \(\frac{mass}{Molar mass}\)
= \(\frac{6}{24}\) = \(\frac{1}{4}\) = 0.25 mole
Thus, Number of moles = \(\frac{Number of atoms or molecules}{Avogadro number}\)
n = \(\frac{N}{L}\)
0.25 = \(\frac{N}{(6.02\times 10\(^{23}}\)
N = \(0.25 \times 6.02\times 10\(^{23}\))
N = 1.505 X 10\(^{23}\)
N = 1.51 X 10\(^{23}\)
There is an explanation video available .