Question

1. A chemist has 2 samples of hydrates. When heated, they lose a different percentage of their original mass. Are they the same or different hydrates? Explain.

2. Cobalt chloride paper is used to test for the presence of water leaking through tiny
cracks in pipes or porcelain.
A. When moisture is present, the test paper goes from blue to pink. Which color
is the hydrated form of cobalt chloride and which color in the anhydrous form?
B. Cobalt chloride paper is carcinogenic. What does that mean? Explain why the
paper should be handled with care

Answer 1

1.The two samples of hydrates are likely to be different hydrates. Hydrates are compounds that contain water molecules that are chemically bound to another compound, and each hydrate can have different properties, including their water content and their mass loss when heated. The fact that the two samples lose a different percentage of their original mass when heated suggests that they are different hydrates.

2.A. The hydrated form of cobalt chloride is pink or red, and the anhydrous form is blue. B. Carcinogenic means that a substance has the potential to cause cancer. The cobalt chloride paper should be handled with care because it can be toxic if ingested or inhaled, and it can cause skin and eye irritation.