What are the four classifications of matter?

of those four, which two are pure substances?

The mass of a substance is independent of the amount of the substance, while density depends on the amount of the substance.

Answer the following question by entering the numeric value with appropriate units. if the length of one side of a square is 12.0 m, what is the perimeter of the square?

Where are valves found?

What changes in physical properties can be used as evidence that a chemical reaction has occured?

The oxidation numbers of nitrogen in nh3, hno3, and no2 are, respectively:

Reactions that affect the nucleus of an atom are called? A. Fusions B. Radioactive decays C. Nuclear reactions D. Fissions

The amplitude of a wave is most directly related to what wave characteristic? Crest length Frequency Wavelength Wave height

Why is oil unable to dissolve well in water? Water is polar and oil is nonpolar, which means they have no attraction for each other. Oil molecules are too large to fit between the closely spaced water molecules in the liquid state.

The fertilizer ammonium sulfate is prepared by the reaction between ammonia and sulfuric acid. How many kg of ammonia are needed to produce 1x10^5 kg of (NH4) 2SO4?

The conversion of chemical energy to mechanical energy is best described by which example? A. sunlight warming the ground B. electricity boiling water C. fuel being combusted to power a rocket