Question

Fill in the blanks
Freezing mixture contains _________ and __________.

Answer 1

Hint: Freezing mixtures are the combination of two or more components whose freezing point is lower than its constituents. The components may be solid, liquid or both. These are used mainly in laboratories to maintain low temperatures.

Complete step by step answer:
When the substances are mixed to form freezing mixture, it absorbs the melting heat. The components are used in certain quantities to attain the lowest temperature.
Water, ice, snow, salts, alcohols and acids can form freezing point mixtures and it attain a temperature of $ - {50^ \circ }{\text{C}}$. The salts in dilute acid solution can decrease the temperature more than the salts in a water solution.
Generally, freezing mixture contains salt and ice. It may also contain dry ice and alcohol. These are used generally to attain a temperature below the freezing point of water.
When salt and ice are mixed, it will not be in equilibrium. Thus the ice melts and salt gets dissolved in water. When the salt is dissolved, heat is absorbed. This heat is taken from the salt solution or surroundings. If the heat is from the salt solution, then its temperature is decreased and if it is from surroundings, then the temperature of the surroundings will be decreased.
Freezing point depression occurs when a component is mixed with the solvent. When a component is freezed, it gets separated into solute crystals and solvent crystals.
freezing mixture contains salt and ice

Note:
Freezing mixture can also be used for deicing. Sodium chloride is used to melt ice. When it is dissolved in water, it decreases the melting point. This is due to the freezing point depression. Thus we can say that salt can prevent melting ice from refreezing.