Science Terms

Question 1

Define: Acid

Answer 1

A substance with a pH less than 7.

Question 2

Define: Acid-carbonate Reaction

Answer 2

A neutralization reaction that produces a salt, water and carbon dioxide gas.

Question 3

Define: Acidification

Answer 3

An increase in the concentration of hydrogen ions in a substance.

Question 4

Define: Alkali

Answer 4

A base that dissolves in water.

Question 5

Define: Base

Answer 5

A substance with a pH greater than 7.

Question 6

Define: Caustic

Answer 6

Able to burn or corrode, especially living materials such as skin.

Question 7

Define: Corrosive

Answer 7

Able to damage or destroy another substance by a chemical reaction.

Question 8

Define: Distilled Water

Answer 8

A substance with equal numbers of hydrogen ions and hydroxide ions.

Question 9

Define: Hydrogen Ion

Answer 9

An ion that is released by acids in solution.

Question 10

Define: Hydroxide Ion

Answer 10

An ion that is released by bases in solution.

Question 11

Define: Indicator

Answer 11

Any substance that changes color when mixed with an acid or base.

Question 12

Define: Ion

Answer 12

An atom or molecule with a net charge.

Question 13

Define: Litmus

Answer 13

A dye that turns red in acidic solutions and blue in alkaline solutions.

Question 14

Define: Neutral Substance

Answer 14

A substance with a pH of 7.

Question 15

Define: Neutralization

Answer 15

A reaction between an acid and a base to produce a salt and water.

Question 16

Define: pH Scale

Answer 16

The standard way of measuring the strengths of acids and bases.

Question 17

Define: Reactive

Answer 17

Tending to chemically interact with other substances.

Question 18

Define: Solution

Answer 18

A type of mixture formed when one substance dissolves in another.

Question 19

Define: Strong Acid

Answer 19

A substance with a pH of 0-3.

Question 20

Define: Strong Base

Answer 20

A substance with a pH of 11-14.

Question 21

Define: Universal Indicator

Answer 21

A dye that turns many different colors at different pH values.

Question 22

Define: Weak Acid

Answer 22

A substance with a pH of 4-6.

Question 23

Define: Weak Base

Answer 23

A substance with a pH of 8-10.

Question 24

Define: Atom

Answer 24

The smallest particle of an element.

Question 25

Define: Atomic Number

Answer 25

The number of protons in an atom.

Question 26

Define: Charge

Answer 26

An electrical property of matter.

Question 27

Define: Electron

Answer 27

A very small subatomic particle with negative charge.

Question 28

Define: Electron Cloud Model

Answer 28

A model of the atom in which electrons move freely.

Question 29

Define: Element

Answer 29

A substance made up of only one type of atom.

Question 30

Define: Elementary Particle

Answer 30

A particle which, in the present state of knowledge, cannot be described as compound, and is thus one of the fundamental constituents of all matter.

Question 31

Define: String Theory

Answer 31

A theory of elementary particles based on the idea that the fundamental entities are not pointlike particles but finite lines, known as strings, or closed loops formed by strings.

Question 32

Define: Fundamental Forces

Answer 32

The four basic forces of nature: the gravitational force, the electromagnetic force, and the two nuclear forces, the strong force and the weak force.

Question 33

Define: Gravitational Force

Answer 33

The force on a particle due to its gravitational attraction to other particles.