Question

How many grams of O2 can be prepared from the thermal decomposition of 4.09kg of H2O

Answer 1

Answer – We are given, mass of H₂O = 4.09 kg

We know thermal decomposition of water is as follow –

2 H₂O -----> 2 H₂ + O₂

Now we need to calculate the moles of water

We know,

Moles = given mass / molar mass

Now we need to convert the given mass kg to g

1 kg = 1000 g

So, 4.09 kg = ?

= 4090 g

Moles of H₂O = 4090 g / 18.015 g.mol^-1

                        = 227.033 moles

From the balanced reaction

2 moles of H₂O = 1 moles of O₂

So, 227.033 moles of H₂O = ? moles of O₂

= 113.5 moles of O₂

We also know,

Mass= moles * molar mass

So, mass of O₂ = 113.5 moles * 31.998 g/mol

                          = 3632.3 g

So, 3632.3 grams of O2 can be prepared from the thermal decomposition of 4.09kg of H₂O.