You are presented with a white solid and told that due to careless labeling it is not clear if the substance is barium chloride, lead chloride, or zinc chloride. when you transfer the solid to a beaker and add water, the solid dissolves to give a clear solution. next a na2so4(aq) solution is added and a white precipitate forms. what is the identity of the unknown white solid?

The given salts are Barium chloride, lead chloride and zinc chloride.

The balanced chemical reaction between barium chloride and sodium sulfate:

The balanced chemical reaction between lead chloride and sodium sulfate:

The balanced chemical reaction between zinc chloride and sodium sulfate:

Both Barium chloride and lead chloride produce a white precipitate of their respective sulfates upon reaction with sodium sulfate. But BaCl2 is readily soluble in water where as Lead chloride is insoluble in water.

Therefore, the compound is barium chloride.

Double displacement reaction is defined as the reaction in which two ionic compounds exchange their anions or cations to form precipitate, salt, or water. The compound barium chloride will form white solid precipitate known as barium sulphate.

The given compounds are barium sulphate, lead chloride, and zinc chloride. These compounds when react with sodium sulphate, will result in different types of products. The chemical reactions for the given compounds are as follows:

Reaction between barium chloride and sodium sulphate is:

The precipitate of barium sulphate is formed along with sodium chloride. The white precipitate settles done in the beaker, whereas sodium chloride remains dissolved in water.

Reaction between lead chloride and sodium sulphate is:

The precipitate formed is also of white colour, known as lead sulphate. The sodium chloride is also formed in the reaction that remains dissolved in solution.

Reaction between zinc chloride and sodium sulfate:

The compounds of zinc chloride and sodium sulfate formed in aqueous solution are sodium chloride and zinc sulfate.

Form the above equation, it is clear that barium chloride compound forms white precipitate that is dissolvable in the water. The white precipitate of lead sulphate is insoluble in the water.

Therefore, the identity of the white solid is barium sulphate.

To know more about precipitation, refer tot he following link:

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the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.