Acid is not any single substance but a "family of substances. There are many different acids. Some are solids, some are liquids, some are gasses.
it is a solid.
Sulfuric acid is a liquid at room temperature.
it is a solid at some points and a liquid at others.
Acetic acid melts at about 16 - 170C, so commonly it is a liquid, but will become a solid below this temp.
solid is it?
Heat is added to a solid to make a liquid... this is called melting. some additional liquid (water,ethanol,acid…) also change solid into a liquid.
Vegetable oils are liquid at room temp, while animal fats are solid.
Malic acid is a solid at room temperature. It is a white crystalline powder that is commonly used as a food additive to give a sour taste.
Nothing, they simply intermix as a solid and liquid form a suspension.
Yes, at certain temperatures and pressures acetic acid is a solid.
The factors that influence whether a fatty acid is liquid or solid include the length of the fatty acid chain (longer chains are more likely to be solid), the degree of saturation (saturated fats are more likely to be solid), and the presence of cis or trans double bonds (trans fats tend to be solid at room temperature).
A solvent is that which may dissolve a solid. Water, hydrochloric Acid, and alcohol are some (times) solvents.