Calculate the number of moles for thefollowing:(i) 52 g of He (finding

1.	Calculate the number of moles for thefollowing:(i) 52 g of He (finding mole frommass)(ii) 12.044*10^23 number of He atoms(finding mole from number ofparticles).
Answer» No. of Moles =Mass in gm Molar mass =52 4 = 13 moles One mole of any element contains 6.022 X 10^23 atoms of the element. Thus 1 mole of He atom consists of 6.022 X 10^23 atoms of He. Thus 6.022 X 10^23 atoms of He = 1 mole of He atom 1 atom of He = 1 / ( 6.022 X 10^23) moles of He So 12.044 X 1023 atoms of He = ( 1 X 12.044 X 10^23) / ( 6.022 X 10^23) moles of He = 2 moles of He atom Thus there are 2 moles of He atom in 12.044 X 10^23 atoms of He.

Calculate the number of moles for thefollowing:(i) 52 g of He (finding mole frommass)(ii) 12.044*10^23 number of He atoms(finding mole from number ofparticles).

Answer»

No. of Moles =Mass in gm Molar mass =52 4 = 13 moles

One mole of any element contains 6.022 X 10^23 atoms of the element. Thus 1 mole of He atom consists of 6.022 X 10^23 atoms of He. Thus

6.022 X 10^23 atoms of He = 1 mole of He atom

1 atom of He = 1 / ( 6.022 X 10^23) moles of He

So 12.044 X 1023 atoms of He = ( 1 X 12.044 X 10^23) / ( 6.022 X 10^23) moles of He

= 2 moles of He atom

Thus there are 2 moles of He atom in 12.044 X 10^23 atoms of He.