Exam #1 definitions

Question 1

anything that occupies space and hay s mass

Answer 1

matter

Question 2

a form of matter that has definite composition and distinct properties

Answer 2

substance

Question 3

a systematic approach to research

Answer 3

scientific method

Question 4

a tentative explanation for a set of observations

Answer 4

hypothesis

Question 5

a concise statement of a relationship between phenomena that is always the same under the same conditions

Answer 5

law

Question 6

a unifying principle that explains body of facts and/or those that are based on them

Answer 6

theory

Question 7

a combination of two or more substances in which the substances retain their distinct identities

Answer 7

mixture

Question 8

composition of the mixture is the same throughout

Answer 8

homogeneous mixture

Question 9

composition of the mixture is not uniform throughout

Answer 9

heterogeneous mixture

Question 10

used to separate a mixture into its pure components

Answer 10

physical means

Question 11

a substance that cannot be separated into simpler substances by chemical means

Answer 11

element

Question 12

a substance composed of atoms of two or more elements chemically united in fixed proportions

Answer 12

compound

Question 13

what can compounds only be separated into?

Answer 13

their pure components (elements) by chemical means

Question 14

does not alter the composition or identity of a substance

Answer 14

physical change

Question 15

alters the composition or identity of the substance involved

Answer 15

chemical change

Question 16

depends upon how much matter is being considered

Answer 16

extensive property

Question 17

what do extensive properties include?

Answer 17

Mass, length and volume

Question 18

does not depend upon how much matter is being considered

Answer 18

intensive property

Question 19

what do intensive properties include?

Answer 19

density, temperature and color

Question 20

measure of quantity of matter

Answer 20

mass

Question 21

force that gravity exerts on an object

Answer 21

weight

Question 22

elements composed of extremely small particles

Answer 22

atoms

Question 23

what are all atoms of a given element?

Answer 23

identical, same size, mass and chemical properties

Question 24

what are atoms of one element compared to all other elements?

Answer 24

different

Question 25

composed of atoms of more than one element

Answer 25

compound

Question 26

in any compound what is the ratio of the numbers of atoms of any two of the element present?

Answer 26

either an integer or a simple fraction

Question 27

involves only the separation, combination and rearrangement of atoms.

Answer 27

chemical reaction

Question 28

what does chemical reactions no result in?

Answer 28

their creation or destruction

Question 29

number of protons in the nucleus

Answer 29

atomic number (Z)

Question 30

number of protons + neutrons

Answer 30

mass number (A)

Question 31

atoms of the same element (X) with different numbers of neutrons in their nuclei

Answer 31

isotopes

Question 32

an aggregate of two or more atoms in a definite arrangement held together by chemical forces

Answer 32

molecules

Question 33

contain two atoms

Answer 33

diatomic molecule

Question 34

contains more than 2 atoms

Answer 34

polyatomic molecule

Question 35

an atom, or group of atoms that has a net positive or negative charge

Answer 35

ion

Question 36

ion with a positive charge

Answer 36

cation

Question 37

if a neutral atom loses one or more electrons what does it become?

Answer 37

a cation

Question 38

ion with a negative charge

Answer 38

anion

Question 39

if a neutral atom gains one or more electrons what does it become?

Answer 39

an anion

Question 40

contains only one ion

Answer 40

monatomic ion

Question 41

shows the exact number of atoms in each element in the smallest unit of a substance

Answer 41

molecular formula

Question 42

shows the simplest whole number ratio of the atoms in a substance

Answer 42

emperical formula

Question 43

consists of a combinations of cations and anions

Answer 43

ionic compounds

Question 44

what must the sum of the charges on the cations and anions in each formula unit equal?

Answer 44

zero

Question 45

what are ionic compounds often?

Answer 45

metal and non metal

Question 46

what do you add to an ionic anion compound?

Answer 46

ide

Question 47

can be identified as a substance that yields hydrogen ions (H+) when disolved in water (HCl gas and HCl in water)

Answer 47

acids

Question 48

compounds that have a specific number of water molecules attached to them

Answer 48

hydrates

Question 49

branch of chemistry that deals with carbon compounds

Answer 49

organic chemistry

Question 50

what does the law of constant composition apply to?

Answer 50

compounds

Question 51

what does the nucleus of an atom contain?

Answer 51

protons and neutrons

Question 52

what do different isotopes of a single element have the same of?

Answer 52

protons

Question 53

what element does not exist as diatomic molecules at room temp and atmospheric pressure?

Answer 53

sulfur

Question 54

what did Rutherford's gold foil experiment lead to?

Answer 54

the nucleus model of the atom

Question 55

strontium

Answer 55

Sr

Question 56

uranium

Answer 56

U

Question 57

cadmium

Answer 57

Cd

Question 58

what is the number of neutrons in an atom equal to?

Answer 58

mass number - atomic number

Question 59

in a cathode ray tube how do electrons pass?

Answer 59

from the cathode to the anode