A sample of hydrated calcium sulfate has a mass of 20.88 g. After it is heated, it has a mass of 16.51 g. What is the percentage by mass of water in the hydrate

When the supply of oxygen is limited, iron metal reacts with oxygen to produce a mixture of and. in a certain experiment, 20.00 g iron metal was reacted with 11.53 g oxygen gas. after the experiment, the iron was totally consumed, and 3.

Reducing the volume of a contained gas by one third, while holding temperature constant, causes pressure to A. be decreased by two thirds. B. be increased by two thirds. C. be decreased by one third. D. be increased by one third

Which of these metals is least likely to be involved in chemical reactions? A. iron B. tin C. gold D. copper

The ideal gas law shows us how a gas will behave under many conditions. The formula is: P V = n R T Where P = pressure, V = volume, n = amount of the substance, R = ideal gas constant, and T = temperature.

Who was the first person to propose that atoms existed?

How many milliliters of a 0.7% stock solution are required to make 2 l of 0.2% solution? how many ml of solvent will be required to carry out the dilution?

What percentage of the naphthalene molecules emitted a photon?

In an endothermic reaction, heat is absorbed from the surroundings. How does this affect entropy? A. The particles in the surroundings move slower and have decreased entropy. B.

The temperature of a sample of liquid water changes from 50°C to 30°C. Which statement best explains the change that must happen at the molecular level? A. The molecules move more quickly and their average kinetic energy increases. B.

The most important reason why solid sodium hydroxide is not used as a primary standard is