A lump of chromium (Cr) has a mass of 95.3 grams and a temperature of 90.5oC. It is placed into a calorimeter with 75.2 mL of water at 20.5oC. After stirring, the final temperature of the water, Cr metal, and calorimeter is 28.6oC. What is the specific heat of Cr metal?

(a) Na2CO3 and AgNO3- Precipitate formed.

Na2CO3 (aq) + 2 AgNO3 (aq) → 2 NaNO3 (aq) + Ag2CO3 (s)

Silver carbonate is the precipitate formed

(b) NaNO3 and NiSO4-No Precipitate formed

(c) FeSO4 and Pb(NO3)2 -Precipitate formed.

FeSO4 (aq) + Pb(NO3)2 (aq) → Fe(NO3)2 (aq) + PbSO4 (s)

Lead sulfate (PbSO4) is the precipitate formed in the reaction

Precipitation reactions refers to the formation of an insoluble salt when two solutions containing soluble salts are combined.

The insoluble salt that is formed is known as the precipitate, hence the name of the reaction.