Question

An aqueous solution of $BaBr{}_{2}$ give yellow ppt with:
A.$K{}_{2}CrO{}_{4}$
B.$AgNO{}_{3}$
C.Both (a) and (b)
D.None of these

Answer 1

Hint: Precipitation reaction is defined as the formation of insoluble salts when two solutions containing soluble salts combine. The insoluble salts known as precipitate. Precipitation reaction can help to determine the presence of various ions in solution. Some examples of precipitation are rain, hail, sleet and snow.

Complete step by step answer:
First we will discuss about the chemical which is given in question,
Barium bromide is the chemical compound with formula $BaBr{}_{2}$. It is dissolved in water and is toxic. The barium bromide can be prepared by treating barium sulphate and barium carbonate with hydrobromic acid.
Then Barium bromide is treated with aqueous solution and heated at ${{120}^{0}}C$ to form anhydrous salt.
Potassium dichromate an inorganic compound with formula $K{}_{2}CrO{}_{4}$. It is also known as dipotassium monochromate or potassium chromate. It is soluble in water and used as oxidizing agents. It appears as a crystalline solid which is yellow in colour. It has no smell and better taste. When potassium chromate is heated it emits chromatic fumes that are toxic.
Silver nitrate is an inorganic compound with formula $AgNO{}_{3}$ . It is far less sensitive to light than the halide. It can be prepared when silver reacts with nitric acid, as a result silver nitrate, water and oxide of nitrogen is formed.
Now we will discuss about the chemical reaction,
Barium bromides is aqueous solution and when potassium dichromate is reacted with barium bromide gives yellow ppt of barium chromate.
$K{}_{2}CrO{}_{4}+BaBr{}_{2}\to BaCrO{}_{4}+2KBr$
Potassium dichromate +barium bromide → barium chromate +potassium bromide
Second, when barium bromide is reacted with silver nitrate gives light yellow ppt of silver bromide.
$2AgNO{}_{3}+BaBr{}_{2}\to Ba\left( NO{}_{3} \right){}_{2}+2AgBr$
According to the reaction, option C is correct.


Note:
Precipitation reaction can be used for the qualitative inorganic analysis. It can be used for making pigments and removing metal ions from aqueous solution. Precipitation may also occur when an antisolvent (a solvent in which the product is insoluble) is added, reducing the solubility of the desired product.