Your problem is based on a topic of chemistry known as stoichiometry.

You will need the atomic wt. Of H and O. They are respectively H=1 and O=16.

The calculations are as follows and are based on Avagodros number which gives us the number of molecules in 1 mole of any element:

1 mole=6.0223 X 10

C.) This is very similar to A

150 molecules of O

I hope this answer's your questions, good luck.

You will need the atomic wt. Of H and O. They are respectively H=1 and O=16.

The calculations are as follows and are based on Avagodros number which gives us the number of molecules in 1 mole of any element:

_{ }A.)1 mole=6.0223 X 10

^{23}molecules of any element, therefore the calculation is 100 molecule x 1 mole/6.0223 X 10^{23}molcules /mole=1.06603 x 10^{-22}mole of water present in 100_g of H20_{B.) }2H=1 and O=16, therefore 2H=2_g/mole and O=16_g/mole then add H and O for a ttl of 18_g/mole of water._{}For the number of moles present in 100_g of water divide 100_g/16_g =6.25 moles of water present in 100_g of H_{2}OC.) This is very similar to A

150 molecules of O

_{2}to moles is 150 molecules X 1 mole/6.0223 x 10^{23}molecules=2.4907 X 10^{-22}moles of O_{2}to five significant figuresI hope this answer's your questions, good luck.

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