Unit 2 Chemistry AW

Question 1

Atoms

Answer 1

The basic unit of a chemical element

Question 2

Molecules

Answer 2

a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.

Question 3

Substances

Answer 3

a particular kind of matter with uniform properties.

Question 4

Homogenous Mixtures

Answer 4

It is the type of mixture where the composition is constant throughout or the components that make up the mixture are distributed uniformly

Question 5

Heterogenous Mixtures

Answer 5

a mixture where throughout the solution the composition is not uniform.

Question 6

Chemical Properties

Answer 6

a characteristic of a substance that may be observed when it participates in a chemical reaction.

Question 7

Physical Properties

Answer 7

a characteristic of a substance that can be observed or measured without changing the identity of the substance

Question 8

Isotopes

Answer 8

Atoms with the same number of protons but different numbers of neutrons

Question 9

Elements

Answer 9

a simple substance that cannot be broken down into smaller parts or changed into another substance.

Question 10

Compounds

Answer 10

a thing that is composed of two or more separate elements; a mixture.

Question 11

Reactants

Answer 11

a chemical substance that is present at the start of a chemical reaction

Question 12

Products

Answer 12

the species formed from chemical reactions

Question 13

Hydrogen Bonds

Answer 13

an electrostatic attraction between a hydrogen atom in one polar molecule (as of water) and a small electronegative atom (as of oxygen, nitrogen, or fluorine) in usually another molecule of the same or a different polar substance.

Question 14

Covalent Bonds

Answer 14

the mutual sharing of one or more pairs of electrons between two atoms

Question 15

Ionic Bonds

Answer 15

the bond formed by the complete transfer of valence electron to attain stability.

Question 16

Cation

Answer 16

an ion, or charged particle, with a positive charge

Question 17

Anion

Answer 17

an atom that has more electrons than protons

Question 18

Periodic
Table

Answer 18

organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic number

Question 19

Periodic Table Rows

Answer 19

organizes chemical elements in rows

Question 20

Volence Electrons

Answer 20

the electrons located at the outermost shell of an atom

Question 21

pH Scale

Answer 21

measures how acidic or alkaline a substance is.

Question 22

Acids

Answer 22

a chemical substance that neutralizes alkalis, dissolves some metals, and turns litmus red; typically, a corrosive or sour-tasting liquid of this kind.

Question 23

Bases

Answer 23

any substance that in water solution is slippery to the touch, tastes bitter, changes the color of indicators