Predict if the following will dissolve in water..? Please explain?

Question

Question: Predict if the following matter will dissolve in water. Give reasons for your prediction.

a. methane gas (CH4)

b. CO2 gas

c. NH3

I'm at a bit of a loss.

Answer 1

1.as for a above it will not

2.co2 gas will not as well

3.NH3 will dissolve in water.

good luck.

Answer 2

Lulz. Looks like someone is cheating on their homework.

Answer 3

methane poor to form hydrogen bonding will not dissolve.

co2 dissolves to some extent concider carbonated drinks.

NH3 dissolves in fairly good amount as NH4OH forming enough hydrogen bonds.

Answer 4

For something to dissolve in water it needs to be able to hydrogen bond to the water molecules.  To figure out if it will H-bond you need to look at the charge distribution on the molecules.  To determine if the charges will be evenly distributed you need to look at the electronegativity (EN) of each atom. Take water for example, the oxygen has a slightly negative charge associated with it, the hydrogens a slightly positive charge, as oxygen has a higher EN then hydrogen.  The negatively charged oxygen will H-bond with adjacent positive hydrogens.  Now look at methane.  The charge is evenly distributed between the constituent atoms, i.e. the charge on the H's is the same as the carbon as their ENs are very similar, so H-bonding will not be possible.   WIth CO2, oxygen is slightly more EN than carbon so it will pull more electron density towards it so you would expect it to be at least partially soluble in water (which it is as evidenced by carbonated drinks).  Finally if you look at ammonia, nitrogen's EN is 3, hydrogens is 2.1 so nitrogen will pull electron denisty towards it giving it a slightly negative charge, and as the hydrogen's electrons are being pulled away from itself, towards the nitrogen atom it will have a slightly positive charge.  It can therefore H-bond with water and willl therefore be soluble.