Question 1 (1 point)
How many atoms are in 223 g of cesium?
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Answer : The correct option is (b) [tex]1.01\times 10^{24}[/tex]
Explanation : Given,
Mass of cesium = 223 g
Molar mass of cesium = 133 g/mole
First we have to calculate the moles of cesium.
[tex]\text{Moles of cesium}=\frac{\text{Given mass cesium}}{\text{Molar mass cesium}}[/tex]
Now putting all the given values in this formula, we get:
[tex]\text{Moles of cesium}=\frac{223g}{133g/mol}=1.67mol[/tex]
Now we have to calculate the number of atoms of cesium.
As, 1 mole of cesium contains [tex]6.022\times 10^{23}[/tex] atoms of cesium
So, 1.67 mole of cesium contains [tex]1.67\times 6.022\times 10^{23}=1.01\times 10^{24}[/tex] atoms of cesium
Therefore, the number of atoms of cesium are [tex]1.01\times 10^{24}[/tex]