Question

how many covalent bonds are present in 9g of H20

Answer 1

Covalent bond is nothing but Bond formed by sharing of electrons between 2 atoms,

So, First of all Remember this, Weight is not related to no.of Covalent bonds, It depends on the atoms which are present in the molecule, and also it depends on no. of electrons participating in the sharing,

In H₂O , Each hydrogen atom needs 1 more electron to get nearest noble gas configuration,

And the oxygen needs 2 more electrons to get nearest noble gas configuration,

So Oxygen shares a electrons with 2 hydrogen atoms, and covalent bonds forms,

As I said before, The Covalent bond depends on no. of electrons participating in the sharing, 

Here 2 electrons from Oxygen atom, and 2 electrons from Hydrogen atoms,

1 forms with 1, So 4 electrons make up 2 covalent bond,

So therefore the answer to your question is 2 covalent bonds,

Hope you understand, Have a great day !