Draw a lewis structure for c2h3cl. show all unshared electron pairs. none of the atoms bears a formal charge, and all atoms have octets (except for hydrogen atoms, which have duets).

See picture below

Explanation:

To do this, we first need to know how are the bonds in this molecule are. To do so, let's calculate the number of insaturations in the molecule:

n°I = C+1 - (H-N+X)/2

These numbers indicate if the molecule has double bond, triple bond, ring, cyclo, among other options:

n°I = 3 - (3+1)/2

n°I = 1

As it's a very small molecule, we can assume this molecule only have a double bond, and it's an alkene.

So the lewis structure, shows the electrons and the bonding, and also shows the unshared electron pairs, depending on how much electron have each molecule.

In the case of carbon:

[C] = [He] 2s2 2p2 ----> 4 electrons

[H] = 1s1 ----> 1 electron

[Cl] = [Ne] 3s2 3p5 ----> 7 electrons.

Therefore, we also know that Carbon has a double bond, so, the main molecule would have something like this:

C = C

so next to the carbons, we can put two hydrogens and in the other carbon, the chlorine and the remaining hydrogen.

See picture below for structure:

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.