Which of the following pairs of aqueous solutions will react to produce a precipitate when mixed together?

Li2SO4 and SrCl2.

Explanation:

Hello,

In this case, reviewing the solubility of the formed salts in each case, we find:

Sodium chloride: very soluble.

Strontium sulfate: very insoluble.

sodium bromide and potassium chloride: very soluble.

Lithium chlorate: very soluble.

In such a way since the formed strontium sulfate, due to the reaction between lithium sulfate and strontium chloride, is very insoluble in water, such reaction will form the required precipitate.

Best regards.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.