UNIT 2- Chemistry JAC

Question 1

Atoms

Answer 1

the basic building block of chemistry

Question 2

Molecules

Answer 2

made up of one or more atoms

Question 3

substance

Answer 3

physical material from which something is made or which has discrete existence

Question 4

homogeneous mixtures

Answer 4

one whose composition is uniform throughout the mixture

Question 5

homogeno us mixtures

Answer 5

one whose composition is uniform throughout the mixture

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 property

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 basic part of a whole

Question 10

compounds

Answer 10

a substance made from two or more different elements that have been chemically joined.

Question 11

Reactants

Answer 11

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

Question 12

products

Answer 12

any item or service you sell to serve a customer’s need or want

Question 13

Hydrogen bonds

Answer 13

a weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other.

Question 14

valence electrons

Answer 14

the electrons located at the outermost shell of an atom

Question 14

covalent bonds

Answer 14

the interatomic linkage that results from the sharing of an electron pair between two atoms

Question 15

anion

Answer 15

Those with a negative charge

Question 15

periodic table- groups

Answer 15

the organized array of all the chemical elements in order of increasing atomic number

Question 15

Ionic bounds

Answer 15

type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound

Question 15

cation

Answer 15

An anion may be defined as an atom or molecule that is negatively charged. A cation may be defined as an atom or molecule that is positively charged

Question 16

periodic table rows

Answer 16

seven horizontal rows, called periods or series

Question 17

Bases

Answer 17

Foundation or main support of something.

Question 18

PH scale

Answer 18

measures how acidic or alkaline a substance is

Question 19

Acids

Answer 19

A chemical that gives off hydrogen ions in water and forms salts by combining with certain metals