CHAPTER 2

Question 1

particles much smaller than the atom

Answer 1

Subatomic particle

Question 2

the smallest particle that has all the properties of an element.

Answer 2

Atom

Question 3

-an element was composed of identical atoms that reacted the same way chemically.
- eye and hook affair

Answer 3

John Dalton

Question 4

first periodic table of the elements.

Answer 4

Dmitri Mendeleev

Question 5

Group 1
Group 7
Group 8 are called?

Answer 5

Alkali metals
Halogens
Noble gasses

Question 6

all soft metals that combine readily with oxygen and react violently with water.

Answer 6

alkali metals,

Question 7

are easily vaporized and combine with metals to form water-soluble salts.

Answer 7

Halogens

Question 8

are highly resistant to reaction with other elements

Answer 8

Noble gasses

Question 9

He concluded that electrons were an integral part of all atoms. He described the atom as looking something like a plum pudding, in which the plums represented nega- tive electric charges (electrons) and the pudding was a shapeless mass of uniform positive electrification

Answer 9

J.J thomson

Question 10

-disproved Thomson’s model of the atom.
-called the center of the atom the nucleus.

Answer 10

Ernest Rutherford

Question 11

improved Rutherford’s description of the atom. His model was a miniature solar system

Answer 11

Neils Bohr

Question 12

The fundamental particles of an atom

Answer 12

electron, the proton, and the neutron.

Question 13

The force that keeps an electron in orbit

Answer 13

centripetal force

Question 14

Through this the electrons maintain their distance from the nucleus while traveling in a circular or elliptical path.

Answer 14

centrifugal force or flying-out-from-the-center force,

Question 15

The strength of attachment of an electron to the nucleus is called the

Answer 15

electron binding energy,

Question 16

-Atoms that have the same atomic number but different atomic mass numbers are
-contain the same number of protons but varying numbers of neutrons.

Answer 16

isotopes.

Question 17

-Atomic nuclei that have the same atomic mass number but different atomic numbers are
-are atoms that have different numbers of protons and different numbers of neutrons but the same total number of nucleons

Answer 17

Isobar

Question 18

-Atoms that have the same number of neutrons but different numbers of protons are
-are atoms with different atomic numbers and different mass numbers but a constant value for the quantity A–Z.

Answer 18

Isotones

Question 19

-have the same atomic number and the same atomic mass number.
-identical atoms except that they exist at different energy states because of differences in nucleon arrangement.

Answer 19

Isomer

Question 20

Atoms of various elements may combine to form structures called

Answer 20

Molecules

Question 21

-is any quantity of one type of molecule
-includes more than one element

Answer 21

Compound

Question 22

the spontaneous emission of particles and energy in order to become stable.

Answer 22

Radioactivity

Question 23

results in emission of alpha particles, beta particles, and usually gamma rays.

Answer 23

Radioactive decay

Question 24

an electron emitted from the nucleus of a radioactive atom.

Answer 24

Beta particle

Question 25

is a helium nucleus that contains two protons and two neutrons.

Answer 25

Alpha particle