Question

a chemist who studies water samples did a demonstration of how to test for lead in water. she added a clear solution of potassium iodide to a clear solution of lead nitrate. then a yellow - looking solid formed in the liquid. what is most likely true about the yellow solid? a. it is solid potassium iodide. b. it is a new substance with different properties. c. it is solid lead nitrate. d. it was secretly added to the test tube by the scientist.

Explanation:

When potassium iodide solution is added to lead nitrate solution, a chemical reaction occurs. A yellow - colored solid (precipitate) is formed, which is lead iodide. This is a new substance formed due to a chemical change, having different properties from the reactants. Potassium iodide is a clear solution initially and lead nitrate is also a clear solution. The solid is not potassium iodide or lead nitrate in their original forms. There is no indication of any external addition by the scientist.

Answer:

B. It is a new substance with different properties.