At room temperature, chlorine is a yellowish gas, bromine is a brown liquid, and iodine is a shiny blue-black solid. Why are these elements considered similar enough to group together on the periodic table?

Light waves are as they pass through the

When utilizing a transmission electron microscope, why is it necessary to stain the specimen with heavy metal salts?

How many grams of oxygen gas will react completely with a block of calcium metal that is 3.0 cm by 3.5 cm by 4.2 cm, if the density of calcium is 1.55 g/ml? show all steps of your calculation as well as the final answer.