A sample of hydrated calcium sulfate has a mass of 2.643 g. After dehydration, the sample has a mass of 2.090 g. What is the percent by mass of water in the hydrate?

Explain how changing the concentration of reactants can affect the rate of reaction.

what action forms a different chemical substance? A. crushing a rock B. burning a piece of wood C. mixing salt and pepper D. melting an ice cube

A certain alcohol contains only carbon, oxygen and hydrogen. When 50 grams are combusted in air, 26.05 grams of C and 6.630 grams of H20 are produced. If the molecular mass of this alcohol is 189 amu, what is its molecular formula?

In a distillation operation, the heat added to the boiler a) increases with increase in reflux ratio b) decreases with increase in reflux ratio c) remains unaltered with change in reflux ratio d) None of the above

Pepsi brand soft drinks contain 38 mg of caffeine (molar mass = 194.19 g/mol) for every serving (355 mL of solution) What is the molarity of caffeine in this solution?

What three relationships are true at equilibrium

What important natural resource do plastics come from? A. trees B. rocks C. minerals D. petroleum

What is a neutral atoms oxidation number

Suppose 30 grams of NaCl are placed in 900 mL of water. What is the molarity of this solution?

After a particularly cold day outside you go home to make some tea. you heat the water in the mug so that botch are about 75 degrees celcious. the tea bag is only 30 degrees celcious and the room is around 26 degrees celcious.