Question
Question: Explain: methanol is more soluble in water than propan-1-ol....
Explain: methanol is more soluble in water than propan-1-ol.
Solution
Methanol is alcohol containing 1 methyl group along with 1 OH group whereas propan-1-ol is compound with a higher number of carbon chains. This information can easily reveal the answer if linked properly to the concept.
Step by step explanation:
In the given question, the concept of solubility is asked in which alcohols solubility is compared and we know alcohol is an organic functional group containing OH as a group and the rest is a carbon chain.
Now the solubility of this alcohol will depend on a few factors which we will discuss. There is a general rule for solubility which is “Like dissolves like” and here we will see how these alcohols are dissolving in water whereas higher alcohols like propan-1-ol does not get dissolved in water.
Methanol is a compound containing alcohol function with 1 Methyl group. So, it has formula i.e. CH3OH and when it is dissolved in the solution, there is hydrogen bonding formed between Methanol and water and as a result it becomes soluble in it. In Methanol, the carbon containing part is non-polar in nature whereas OH is polar in nature.
Becomes soluble due to (R−Oδ−−Hδ+)$$and{\text{ }}water{\text{ }}\left( {{\text{ }}{H^{\delta + }} - {O^{\delta - }} - {H^{\delta + }}} \right)SothepolarOHgroupformshydrogenbondingwith{H_2}Oandtherefore,getsdissolved.Nowifwemovetoalcoholwithhighernumbershavingmorecarbonchains,theyarenotsolubleinwateranditisobservedthatafter4chains,theybecomecompletelyinsoluble.Nowthiscanbeexplained,inhigheralcoholsthenon−polargroupispresentlargeinnumbercomparedtopolargroupsowaterwillformbondingwithOH$$ group but less in number because non-polar group is present in larger numbers.
So, this hydrophobic nature overcomes the hydrophilic nature and as a result solubility in water is lost.
Therefore, methanol is soluble in water and propan-1-ol is not because a larger number of carbons, lower will be solubility in water and also larger the molecular mass, lower will be solubility in water.
Note: To answer solubility related answers, just have some knowledge of types of bonding and forces like Vander-Waals bonding, hydrogen bonding etc. and structure of organic compounds could easily take to the answer when these concepts are linked.