How many atoms are there in 1.45 x 10^-17 mol of arsenic?

To find the number of atom we multiply the

No.of moles number of mole with Avogadro's number.

As 1mole of arsenic contains contains 6.02x10^23 unit of substance which is a constant value e for 1mooe

So;

1.45x10^-17moles contain=6.02x10^23 multiply with 1.45x10^-17

= 8,730,000 atoms of arsenic are present in above mentioned moles of arsenic

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.