chap 1

Question 1

atoms

Answer 1

basic submicroscopic particles that constitute the fundamental building blocks of ordinary matter

Question 2

molecules

Answer 2

substances formed when two or more atoms come together (bond) in specific geometric arrangements

Question 3

pure substance

Answer 3

made up of only one component and its composition is invariant

Question 4

mixture

Answer 4

a substance composed of two or more components in proportions that can vary from one sample to another

Question 5

pure substances can be categorized into what two types?

Answer 5

elements and compounds

Question 6

element

Answer 6

substance that cannot be chemically broken down into simpler substances (basic building blocks of matter)

Question 7

compound

Answer 7

substance composed of two or more elements in fixed definite proportions

Question 8

mixtures can be categorized into two types

Answer 8

heterogenous and homogenous

Question 9

elemts are arranged by what?

Answer 9

their atomic number

Question 10

elements are represented in the periodic table by?

Answer 10

their symbol and atomic number

Question 11

elements within the same column have what?

Answer 11

very similar physical and chemical properties

Question 12

atoms with the same number of protons but different number of neutrons are called

Answer 12

isotopes

Question 13

the sum of the number of neutrons and protons in an atom is its..

Answer 13

mass number

Question 14

the ______ is on the top, and the _______ is on the bottom

Answer 14

mass number, atomic number

Question 15

mass number =

Answer 15

number of protons (p^+) + number of neutrons (n)

Question 16

in chemical changes, atoms can lose or gain electrons and become charged particles called

Answer 16

ions

Question 17

positvely charged ions

Answer 17

cations

Question 18

negatively charged ions

Answer 18

anions

Question 19

atomic mass = E(fraction of isotope n) x (mass of isotope n)