chemistry

Why are bond angles of H2O & NH3 104.5 and 107.5?

🤔Why are bond angles of H2O & NH3 104.5 and 107.5?

According to valence shell electron pair repulsion theory,two types of electron pairs are present around the central atom. 1.Lone pair 2.Bond pair
so:

What is lone pair and bond pair of electrons?

In simple words ,lone pair is the unshared pair of electron and the bond pair is the shared pair of electron.

Trick to find out type of Hybridization in NH3 & H2O:
Both nh3 and h2o are sp3 hydridized but how you can easily find out the type of hybridization.so the simple trick to find out the type of hybridization is to count the total number of lone pair of electrons and sigma bond. If the total number is equal to four hybrid orbitals as you can see in case of ammonia ,we have one lone pair and three sigma bonds results in total of 4 hybrid orbitals indicates sp3 hybridization whereas in case of water we have 2 lone pair and two sigma bond results in total of 4 hybrid orbitals indicates sp3 hybridization. In both NH3 & H2O,The central atom is Sp3 hybridized because NH3 contain 1 lone pair & 3 bond pair (sigma bond) electrons. The lone pair has a greater repulsion Which compresses the bond pairs to an angle Of 107.5 ,resulting in a trigonal pyramidal Structure . Whereas the H2O contain 2 lone pair & 2 bond pair of electrons. The lone pairs exerts greater repulsion on each other & also on bond pairs. As a result ,the bond pairs are compressed together to an angle of 104.5 with an angular shape. Watch a video on YouTube:
👉Why are bond angles of H2O & NH3 104.5 and 107.5?

&


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s