Chapter 1-2

Question 1

Aqueous solution

Answer 1

A solution in which water is the solvent.

Question 2

Atom

Answer 2

The smallest unit of matter that retains the properties of an element.

Question 3

Atomic number

Answer 3

The number of protons in each atom of a particular element.

Question 4

Base

Answer 4

A substance that decreases the hydrogen ion concentration in a solution.

Question 5

Buffers

Answer 5

A chemical substance that resists changes in pH be accepting hydrogen ions from or donation hydrogen ions to solutions.

Question 6

Chemical bonds

Answer 6

An attraction between two atoms resulting from a sharing of outer shell electrons or the presence of opposite charges on the atoms. The bonded atoms gain complete outer electron shells.

Question 7

Chemical reactions

Answer 7

A process leading. To chemical changes in matter, involving the making and/or breaking of chemical bonds.

Question 8

Cohesion

Answer 8

The attraction between molecules of the same kind.

Question 9

Compounds

Answer 9

A substance containing two or more elements in a fixed ratio.

Question 10

Biology

Answer 10

The scientific study of life.

Question 11

Biosphere

Answer 11

The global ecosystem; the entire portion of earth inhabited by life; all of life where it lives.

Question 12

Controlled experiment

Answer 12

A component of the process of science whereby a scientist carries out two parallel tests, an experiment test and a control test. The experimental test differs from the control by one factor, the variable.

Question 13

Discovery science

Answer 13

The process of scientific inquiry that focuses on describing nature.

Question 14

Covalent bond

Answer 14

An attraction between atoms that share one or more pairs of outer shell electrons.

Question 15

Electron

Answer 15

A subatomic particle with a single unit of negative electrical charge.

Question 16

Elements

Answer 16

A substance that cannot be broken down into other substances by chemical means.

Question 17

Evaporative cooling

Answer 17

A property of water whereby a body becomes cooler as water evaporated from it.

Question 18

Heat

Answer 18

The amount of kinetic energy contained in the movement of the atoms and molecules in a body of matter.

Question 19

Hydrogen bonds

Answer 19

A type of weak chemical bond formed when a partially positive molecule is attracted to the partially negative atom in another molecule.

Question 20

Ions

Answer 20

An atom or molecule that has gained or lost one or more electrons, thus acquiring an electrical charge.

Question 21

Ionic bond

Answer 21

An attraction between two ions with opposite electrical charges.

Question 22

Isotopes

Answer 22

A variant form of atom. Isotopes of an element that have the same number of protons and electrons but different number of neutrons.

Question 23

Mass

Answer 23

A measure of the amount of material is in an object.

Question 24

Eukaryotic cell

Answer 24

A type of cell that has a membrane enclosed nucleus and other membrane enclosed organelles. All organisms except bacteria and arches are composed of eukaryotic cells.

Question 25

Ecosystem

Answer 25

All the organisms in a given area along with the non living factors with which they interact; a biological community and it's physical environment.

Question 26

Genes

Answer 26

A unit of inheritance in DNA consisting of a specific nucleotide sequence that programs the amino acid sequence of a polypeptide.

Question 27

Hypothesis

Answer 27

A tentative explainer ion that a scientist proposed for a specific phenomenon that has been observed.

Question 28

Mads number

Answer 28

The sum of the number of protons and neutrons in an atom's nucleus.

Question 29

Matter

Answer 29

Anything that occupies space and has mass.

Question 30

Molecule

Answer 30

A group of two or more atoms held together by covalent bonds.

Question 31

Neutron

Answer 31

An electrically neutral particle.

Question 32

Nucleus

Answer 32

An atom's central core, containing protons and neutrons. The genetic control center of a eukaryotic cell.

Question 33

pH scale

Answer 33

A measure of the relative acidity of a solution, ranging in value from 0 (most acidic) to 14 (most basic).

Question 34

Polar molecule

Answer 34

A molecule containing polar covalent bonds.

Question 35

Products

Answer 35

An ending material in a chemical reaction.

Question 36

Proton

Answer 36

A subatomic particle with a single unit of positive electrical charge.

Question 37

Radioactive isotope

Answer 37

An isotope whose nucleus decays spontaneously, giving off particles and energy.

Question 38

Hypothesis-driven

Answer 38

The process of scientific inquiry that uses the steps of the scientific method to answer questions about nature.

Question 39

Life

Answer 39

The set of common characteristics that distinguish living organisms.

Question 40

Natural selection

Answer 40

A process in which organisms with certain inherited characteristics are more likely to survive and reproduce than are organisms with other characteristics.

Question 41

Prokaryotic cell

Answer 41

A type of cell lacking a nucleus and other organelles.

Question 42

Reactants

Answer 42

A starting material in a chemical reaction.

Question 43

Solute

Answer 43

A substance that is dissolved in a solution.

Question 44

Solution

Answer 44

A liquid consisting of a homozygous mixture of two or more substances.

Question 45

Solvent

Answer 45

The dissolving agent in a solution.

Question 46

Temperature

Answer 46

A measure of the intensity of heat, reflecting the average kinetic energy or speed of molecules.

Question 47

Trace elements

Answer 47

An element that is essential for the survival of an organism but is needed in only minute quantities.

Question 48

Scientific method

Answer 48

Scientific investigation involving the observation of a phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to demonstrate the truth or falseness of the hypothesis, and results that validate or modify the hypothesis.

Question 49

Theory

Answer 49

A widely accepted explanatory idea that is broad in scope and supported by a large body of evidence.

Question 50

Acid

Answer 50

A substance that increases the hydrogen ion concentration in a solution.