Calculate the atomic mass of an element X if it has 3 naturally occurring isotopes: X-20 with an abundance of 90.51% and a mass of 19.992, X-21 with an abundance of 0.27% and a mass of 20.994, and X-22 with an abundance of 9.22% and a mass of 21.991. Using the calculated mass, which element is this likely to be? this is the last question so plz help me

Covalent network solids typically have melting points and boiling points. the chemical formula of a network solid indicates in the molecule.

Achemical reaction (also known as a chemical change) produces substances that are chemically different from the starting materials. an example of a chemical reaction is the formation of water from hydrogen and oxygen gas.in a physical change, a substance changes its physical appearance but not its chemical identity. an example of physical change is the formation of liquid water from solid water, a familiar process called melting. physically, liquid water looks very different from solid water (ice) but the chemical identity, water, is the same for both. which of following changes that affect the composition of our atmosphere involve physical changes and which involve chemical reactions? oxygen gas changes to ozone during thunderstorms carbon dioxide is produced by the combustion of gasoline in an automobile engine. when coal, oil, and natural gas are decomposed in landsills they produce methane gas. freezing rain develops when a warm air mass overrides a cold air mass. fog forms from water vapor when the temperature drops below the dew point

Chemical kinetics what was the rate of reaction in trial 3? choose the closest answer.