Would you expect an organic compound to be soluble in water?why?

Answer 1

Depends on the organic compound. Any molecule containing carbon and hydrogen is considered to be "organic". Note: CO2 (carbon dioxide) does not have hydrogen, so it's not organic, but plays a major role in organic chemisry.

Lets look at two organic compounds: alcohol and ether.
The following examples uses the same number of carbons, hydrogens, and one oxygen.

First TWO carbons:
ethanol (alcohol): fully miscible in water
dimethyl ether: fully miscible in water

Next THREE carbons:
Ethyl methyl ether: limited solubility
Isopropyl alcohol (isopropanol or rubbing alcohol): very solubility
n-Propyl alcohol: soluble

Now FOUR carbons:
Diethyl ether has the formula C4H10O or CH3-CH2-O-CH2-CH3
It is barely soluble in water (7 g/100 ml)

Butanol also has formula C4H10O and several isomers
n-butanol CH3(CH2)3OH 7.7g/100 ml at 20°C 9ml/100ml
sec-butanol CH3CH2CH(OH)CH3 15g/100g water
isobutanol (CH3)2CHCH2OH 8.7g/100ml
tert-butanol (CH3)3COH fully miscible in water

Basically the two factors are chain length and polarity.
Greater chain length less solubility. (More linear carbons)
Greater polarity more solubility. (Alcohols more polar than ethers)

Answer 2

Maybe, maybe not.

Whether or not a compound is soluble in water depends primarily upon the function groups of that compound. It also depends on the size of the compound (i.e., how long is the C backbone of the compound).

Those compounds which tend to be water soluble are: alcohols, ethers, carboxylic acids. This is not exhausive, just some common examples. This is because the functional groups attached to the organic structure (the C-H backbone) are what effect the solubilities. Things like carboxylic acids and alcohols form hydrogen bonds with the water, helping to solubilize it.

Within any group, there will be varying solubilities. Take alcohols for example: methanol, ethanol, and isopropanol are all completely soluble in water. By the time you get to butanol and some of the larger alcohols, including those with more complex structures, they tend to be less soluble.

The earlier answer re: biochemistry is very apt. Most of the non-structural parts of your body are organic, and most of your body is also water....

The answer about rocks, however is completely wrong. "Rocks", and most geological samples, are inorganic. And inorganic compounds, just like organic ones, come in all sorts of solubilities.

Answer 3

Organic compounds contain carbon. Hydrocarbons qualify, but you don't think water mixes with crude oil, do you?

Your body contains organic compounds too, water-soluble and otherwise.

An organic compound may be water-soluble or not. It depends on a lot of factors.

Answer 4

No. Rocks are organic, they aren't soluble in water.

Just becasue it is organic doesn't mean it will be soluble in water.

Answer 5

organic compounds are usually less polar, but as water is more polar, organic compounds will be more soluable in organic solvents like chloroform, benzene etc. and less soluable in water, usually.