What concentration of H+ ions does a substance with a pH of 3 have? 1x10-5 mol/dm3
1x10-2 mol/dm3
1x10-4 mol/dm3
1x10-3 mol/dm3​

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled

If a simple machine aduces the strength of a force, what must be increased? the speed of the input force the work the simple machine performs the size of the simple machine the distance over which the force is applied

How is electrolysis most commonly used to produce an energy source? a - splitting water molecules produces oxygen, which organisms breathe to fuel their bodies. b - splitting water molecules produces hydrogen gas, which is used to power machines through hydrogen fuel cells. c - splitting carbon dioxide molecules produces coal, a form of carbon that can be burned to produce heat. d - splitting carbon dioxide molecules produces natural gas, which can be burned to generate electricity in power plants.