Question

Why is dry ice kept at room temperature and at one atmosphere pressure?

Answer 1

Dry ice is the solid form of carbon dioxide. It is used as a cooling agent, fog machines at theatres for dramatic effects. Its advantages include the lower temperature than that of water ice and not leaving residue.

Complete step by step answer:
Dry ice is kept at room temperature and at one atm pressure to avoid sublimation (solid carbon dioxide sublimes at lower temperatures into large volumes of $CO_{2}$ , gas and is dangerous to handle.
Dry ice at −78.5 C (−109.3°F or 194.7 K) sublimes at the earth’s atmospheric pressure. This extreme cold makes the solid dangerous to handle without protection due to burns caused by freezing.
Dry ice is colorless, non-flammable with sour zesty odor and lowers the pH of solution when dissolved in water due to the formation of carbonic acid. It is non-polar having zero dipole moment so attractive intermolecular van der Waals forces operate.
As a rule, dry ice will sublimate at a rate of 1% per hour. Sublimation of dry ice is an endothermic reaction because the dry ice experiences sublimation and the result is extremely cold which means all of the temperature from the surroundings is being pulled into the substance.

Note:
Dry ice can be very hazardous in a small space, which is not well ventilated. When dry ice melts, it turns to carbon dioxide gas. If enough carbon dioxide gas is present, a person can become unconscious, and in some cases, die.