BeH2 Lewis structure

BeH2 (beryllium hydride) has one beryllium atom and two hydrogen atoms.

In the BeH2 Lewis structure, there are two single bonds around the beryllium atom, with two hydrogen atoms attached to it, and none of the atoms has a lone pair.

Contents

Steps

Here’s how you can easily draw the BeH2 Lewis structure step by step:

#1 Draw a rough skeleton structure
#2 Mention lone pairs on the atoms
#3 If needed, mention formal charges on the atoms

Now, let’s take a closer look at each step mentioned above.

#1 Draw a rough skeleton structure

• First, determine the total number of valence electrons

In the periodic table, beryllium lies in group 2, and hydrogen lies in group 1.

Hence, beryllium has two valence electrons and hydrogen has one valence electron.

Since BeH2 has one beryllium atom and two hydrogen atoms, so…

Valence electrons of one beryllium atom = 2 × 1 = 2
Valence electrons of two hydrogen atoms = 1 × 2 = 2

And the total valence electrons = 2 + 2 = 4

• Second, find the total electron pairs

We have a total of 4 valence electrons. And when we divide this value by two, we get the value of total electron pairs.

Total electron pairs = total valence electrons ÷ 2

So the total electron pairs = 4 ÷ 2 = 2

• Third, determine the central atom

Here hydrogen can not be the central atom. Because the central atom is bonded with at least two other atoms, and hydrogen has only one electron in its last shell, so it can not make more than one bond.

Hence, here we have to assume that the central atom is beryllium.

Therefore, place beryllium in the center and hydrogens on either side.

• And finally, draw the rough sketch

#2 Mention lone pairs on the atoms

Here, we have a total of 2 electron pairs. And two Be — H bonds are already marked. So we do not have to mark any electron pair as a lone pair on the sketch.

And in the above structure, you can see that the central atom (beryllium) doesn’t form an octet. But, beryllium has an exception that it does not require eight electrons to form an octet. So no need to worry about the octet rule here.

Therefore, this structure is the stable Lewis structure of BeH2.

Next: HNO Lewis structure