In an experiment, a student wants to increase the rate of a reaction that involves gases. Which change to the reactants would accomplish this?
Increase the volume to decrease pressure and to increase concentration.
Increase the volume to increase pressure and to decrease concentration.
Decrease the volume to decrease pressure and to increase concentration.
Decrease the volume to increase pressure and to increase concentration.

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

When a septic tank backs up a goes in to clean it out

Stage in which a typical star has completely stopped fusion