Which set of elements form electron precise hydrides?

Give one method for industrial preparation and one for laboratory preparation of $CO$ and $CO_2$ each.

Assertion : $Pb^{4+}$ compounds are stronger oxidizing agents than $Sn^{4+}$ compounds.
Reason : The higher oxidation states for the group $14$ elements are more stable for the heavier members of the group due to 'inert pair effect'.

Which gas is evolved when $SiO_2$ reacts with sodium carbonate?

Which one of the following is a good conductor of electricity?

When lead nitrate is heated,it gives