question:
Some of Earth's water is stored underground in porous rock formations known as aquifers. Which of these could use up groundwater in aquifers?

answer:
excessive pumping from wells

question:
If a neutral atom loses an electron, what is formed?

answer:
An ion

question:
What atoms combine to make up a molecule of water? 1. 1 hydrogen, 1 oxygen 2.

answer:
2 hydrogen, 1 oxygen

question:
In any physical or chemical process, what two quantities are always conserved?

answer:
matter and total energy