Question

What mass in grams of oxygen gas are produced when 2.43 x 10-4 g of KCIO,

are completely reacted according to the following chemical equation:
2 KCIO₂ (s) → 2 KCI (s) + 3 0₂(g)

Answer 1

To solve this problem, we need to use stoichiometry and the molar mass of KCIO4 and O2.

The balanced chemical equation shows that 2 moles of KCIO4 produce 3 moles of O2. Therefore, we can write a ratio of the moles of KCIO4 to moles of O2 as:

2 moles KCIO4 / 3 moles O2

We can use the molar mass of KCIO4 to convert the given mass of KCIO4 to moles:

2.43 x 10^-4 g KCIO4 x (1 mol KCIO4/ 391.28 g KCIO4) = 6.20 x 10^-7 mol KCIO4

Using the mole ratio, we can calculate the number of moles of O2 produced:

6.20 x 10^-7 mol KCIO4 x (3 moles O2 / 2 moles KCIO4) = 9.30 x 10^-7 mol O2

Finally, we can use the molar mass of O2 to convert the number of moles to mass in grams:

9.30 x 10^-7 mol O2 x (32.00 g O2 / 1 mol O2) = 2.98 x 10^-5 g O2

Therefore, the mass of O2 produced is 2.98 x 10^-5 g.