Question

Are acetic acid, ethyl alcohol, vinegar, sodium hydroxide, ammonium hydroxide and hydrochloric acid soluble and flammable? Why is it flammable? Why is it soluble? Why not?

Answer 1

All are soluble in water. It means that a compound dissolves in water, saying in other words, they form one phase upon mixing with water. They are soluble because all of them are polar compounds (NaOH, Acetic acid, NH4OH, HCl) or mixture of polar compounds called ‘vinegar’ (water and acetic acid). As the reagents are polar they should dissolve in polar solvents (water).
Acetic acid and ethyl alcohol are flammable, because they contain carbon and hydrogen atoms in low oxidation state (C-H and C-C bonds), which can be oxidized by oxygen.
Contrary to this, HCl and NaOH contain elements in their stable oxidation state (Na+, O-2, H+, Cl-). Therefore, they don’t react with oxygen being non-flammable.
Despite NH3 and acetic acid are flammable, their diluted aqueous solutions (ammonium hydroxide and vinegar) are considered as non-flammable, because they contain more water than the reagent.