Unit 3 (chapter 4)

Question 1

anion

Answer 1

negative ions formed by gaining electrons

Question 2

atom

Answer 2

particle that consists of a nucleus of protons and neutrons surrounded by a cloud of electrons. distinguished by protons

Question 3

atomic mass

Answer 3

mass of the atom; weighted average of the masses of all naturally occurring isotopes of an element

Question 4

atomic mass unit

Answer 4

a unit of mass used to express atomic and molecular weights (ex: O is 15.999)

Question 5

atomic mass number

Answer 5

mass of protons and neutrons

Question 6

cation

Answer 6

positive ions are formed by losing electrons

Question 7

covalent bond

Answer 7

bond between 2 nonmetals

Question 8

diatomic element

Answer 8

elements that when uncombined with any other element exists as a bonded pair of atoms (1+7 rule)

Question 9

electron

Answer 9

negative charge, 0 amu, found outside nucleus

Question 10

formula unit

Answer 10

ratios of ions held together by ionic bonds

Question 11

ion

Answer 11

• charged particle
• ions are formed from the loss or gain of electrons
• positive ions (cations) are formed by losing electrons
• negative ions (anions) are formed by gaining electrons

Question 12

ionic bond

Answer 12

bond between one metal and one nonmetal

Question 13

ionic compound

Answer 13

• at least one nonmetal and one metal
• made up of formula units

Question 14

isotope

Answer 14

atoms of the same element with different masses (because of difference in number of neutrons)
- have the same physical and chemical properties
- some are radioactive, meaning their nuclei are unstable and emit radiation
- radiation is not detectable by human sense

Question 15

mass number

Answer 15

mass of protons and neutrons

Question 16

metal

Answer 16

a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity

Question 17

metalloid (aka semimetal)

Answer 17

an element whos properties are between metals and nonmetals

Question 18

molecular compound

Answer 18

• 2 or more non-metals
• made up of molecules (neutral groups of nonmetal atoms held together by covalent bonds and connected to each other by intermolecular forces)

Question 19

molecule

Answer 19

neutral groups of nonmetal atoms held together by covalent bonds and connected to each other by intermolecular forces

Question 20

monoatomic ion

Answer 20

an ion consisting of exactly one atom

Question 21

neuton

Answer 21

charge of 0, 1 amu, found inside nucleus

Question 22

nonmetal

Answer 22

dull, found on the right of periodic table

Question 23

nuclear atom

Answer 23

model developed by rutherford
In the nuclear atom, the protons and neutrons, which comprise nearly all of the mass of the atom, are located in the nucleus at the center of the atom. The electrons are distributed around the nucleus and occupy most of the volume of the atom

Question 24

proton

Answer 24

positive 1 charge, 1 amu, found inside nucleus

Question 25

transition metal

Answer 25

any of various chemical elements that have valence electrons—i.e., electrons that can participate in the formation of chemical bonds—in two shells instead of only one

Question 26

atomic number

Answer 26

number of protons

Question 27

Coulomb's Law

Answer 27

describes the strength of the electrostatic force (attraction or repulsion) between two charged objects

Question 28

law of conservation of matter

Answer 28

formulated by Lavoisier, matter cannot be created or destroyed in an isolated system

Question 29

law of constant proportions

Answer 29

created by proust, chemical compounds are made up of elements that are present in a fixed ratio by mass

Question 30

Dalton

Answer 30

created law of multiple proportions and Dalton's atomic theory

Question 31

law of multiple proportions

Answer 31

the same elements can form more than one compound in different whole number ratios

Question 32

Dalton's atomic theory

Answer 32

- matter is made up of atoms - particles or atoms of an element are identical (wrong) - atoms are indivisible (wrong) - there are as many kinds of atoms as elements - atoms can combine to form other elements

Question 33

Michael Faraday

Answer 33

electricity responds to a magnet, charged. cathode has mass

Question 34

Thompson

Answer 34

cathode ray tube, discovered electron and electron charge

Question 35

Millikan

Answer 35

mass of electron, experimental apparatus

Question 36

Thomson

Answer 36

Plum pudding model, atoms have a neutral charge

Question 37

Rutherford

Answer 37

gold foil experiment, alpha particles, positively charged nucleus, discovered protons, nuclear atom model

Question 38

Chadwick

Answer 38

discovered neutrons