Question

Give reason why ch4 is more stable than sih4

Answer 1

As thermal stability decreases down the group -

CH4 > SiH4 > GeH4 > SnH4 > PbH4

here CH4 is natural gas and is stable in air while SiH4 spontaneously bursts into flames when exposed to oxygen.
#hope this helps u. ..

Answer 2

The stability of any chemical compound is heavily dependent on it's chemical bonds and their characteristics.

Similarly,CH4 is more stable than the SiH4 because,the carbon molecule's bond length is much smaller than the Si molecule.

That's why the bonding power of the carbon is also great than the silicon,which makes CH4 more stable than the SiH4.