Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
0 votes

How many molecules of water and oxygen atoms are present in 0.9g of water?

$\begin{array}{1 1}(a)\;3.010\times 10^{22}&(b)\;6.02\times 10^{23}\\(c)\;2.010\times 10^{23}&(d)\;4.01\times 10^{22}\end{array}$

Can you answer this question?

1 Answer

0 votes
Gram-molecular mass of water=18g
Number of moles in 0.9g of water =$\large\frac{0.9}{18}$
$\Rightarrow 0.05$
Number of water molecules in one mole of water=$6.02\times 10^{23}$
Number of molecules of water in 0.05 moles
$\Rightarrow 0.05\times 6.02\times 10^{23}$
$\Rightarrow 3.010\times 10^{22}$
As one molecule of water contains one oxygen atom ,so number of oxygen atoms in $3.010\times 10^{22}$ molecules of water =$3.010\times 10^{22}$
Hence (a) is the correct answer.
answered Oct 22, 2013 by sreemathi.v

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App