Question

somebody wanted to calculate the number of moles of oxygen atoms comprising of 9.033 * 10 raise to 23 number of its atoms .the person further thought to calculate its mass and to find the number of moles of hydrogen atoms required to combine completely with this amount of oxygen to form water find the number of moles of oxygen atoms ,their mass ( in grams ) and the number of moles of hydrogen atoms

Answer 1

number of moles of oxygen is = 9.033*10^23/6.022*10^23= 1.5 moles
1 mole of oxygen = 16 gm
1.5 mole = 16*1.5 = 24gm
in water
O:H = 8:1
so mass of hydrogen will be
(24/3)*1 = 3 gm
mass of 1 mole of hydrogen = 1 gm
so we need 3 moles of hydrogen
in one mole of hydrogen we have = 6.022*10^23 atoms
in 3 moles = 6.022*10^23*3 = 18.066*10^23 atoms
total mass of water formed = 24+3 = 27 gms

Answer 2

Answer; 1.5, 24 and 3 respectively