Question

9. When 3.0 g of carbon is burnt in 8.00 g oxygen, 11.00 g of carbon dioxide is produced. What mass of carbon
dioxide will be formed when 3.00 g of carbon is burnt in 50.00 g of oxygen? Which law of chemical
combination will govern your answer?​

Answer 1

Answer:

First, let us write the reaction taking place here

C + O2 → CO2  

As per the given condition, when 3.0 g of carbon is burnt in 8.00 g oxygen, 11.00 g of carbon dioxide is produced.  

3g + 8g →11 g ( from the above reaction)

 Total mass of reactants = mass of carbon + mass of oxygen

                      =3g+8g=11g

Total mass of reactants = Total mass of products

Therefore, the law of conservation of mass is proved.

Then, it also depicts that the carbon dioxide contains carbon and oxygen in a fixed ratio by mass, which is 3:8.

Thus it further proves the law of constant proportions.

3 g of carbon must also combine with 8 g of oxygen only.

This means that (50−8)=42g of oxygen will remain unreacted.

The remaining 42 g of oxygen will be left un-reactive. In this case also, only 11 g of carbon dioxide will be formed

The above answer is governed by the law of constant proportions.