Radium-221 has a half-life of 30 s. how long will it take for 95% of a sample to decay

66.0g of dry ice (solid carbon dioxide)

Why does moving air over a wet surface make it dry more quickly?

Enter your answer in the provided box. in a 0.740 m solution, a weak acid is 12.5% dissociated. calculate ka of the acid.

Describe the nature and structure of an atom

A 200 g sample of water with a temperature of 32◦C is added to 50 g water at 55◦C in an insulated container. What is the final temperature after thermal equilibrium is reached? The specific heat of water in the liquid state is 4.

According to the second law of thermodynamics, the entropy of any system always increases. According to the second law of thermodynamics, the entropy of any system always increases. True False

If the density of Cu is 8.96g/cm cubed, what is the volume of 28kg of Cu?

A piece of iron can change in different ways. How is iron bending different from iron rusting?

Which organism would least likely be selectively bred A) Dandelions B) Nantes Carrots C) Belgian Blue Cattle D) Hypoallergenic Cats

You are given a clear solution of KNO3. Using 3-4 sentences explain how you would determine if the solution is unsaturated, saturated, or supersaturated