M1

Question 1

Define as half of the distance between the nuclei of neighbouring atoms in the pure element

Answer 1

atomic radii

Question 2

the energy required to remove n electron from a gas-phase atom

Answer 2

ionization energy

Question 3

the energy change that occurs when an electron is attached to an atom in the gas phase to form an negative ion

Answer 3

electron affinity

Question 4

measure of the relative tendency of an atom to attract electrons to itself when it is chemically combined with another atom

Answer 4

electronegativity

Question 5

show some properties that are characteristics of both metals and non-metals

Answer 5

metalloids

Question 6

insulators at lower temperatures but become conductors at higher temperature

Answer 6

semiconductor

Question 7

high terminal conductivity

Answer 7

metals

Question 8

good heat insulators

Answer 8

non-metals

Question 9

which of the following element is the most electronegative?
a. Ca
b. B
c. I
d. F

Answer 9

F

Question 10

the properties of the elements are periodic functions of their atomic numbers

Answer 10

periodic law

Question 11

based on the physical properties

Answer 11

lothar meyer

Question 12

based on the chemical properties

Answer 12

dimitri mendeleev

Question 13

a single electron will occupy an emtpy orbitals first before pairing.

Answer 13

hund’s rule

Question 14

orbitals fill in order of increasing energy, from lowest to highest.

Answer 14

aufbau principle

Question 15

atom in its lowest energy, or unexcuited, state

Answer 15

ground state

Question 16

distribution of electrons

Answer 16

electron configuration

Question 17

the modern atomic model

Answer 17

electron cloud model

Question 18

bombardment of beryllium with high-energy alpha particles produced neutrons

Answer 18

j. chadwick

Question 19

describe the electron of a hydrogen atom as revolving around its nucleus in one of a discreteset of circular orbits

Answer 19

neils bhor

Question 20

proposed the idea of wave-like nature of electron

Answer 20

louis de brogli

Question 21

based on the wave properties of matter

Answer 21

quantum mechanics

Question 22

a region of space in which the probability of finding an electron is high

Answer 22

Atomic orbital

Question 23

The scattering experiment

Answer 23

Ernest Rutherford

Question 24

Saturn-like model

Answer 24

Hantaro nagaoka

Question 25

Positive charged localized in the nucleus

Answer 25

Nuclear model

Question 26

elements of chemical compound are held together by electrical forces.

Answer 26

humpry davy

Question 27

what is the shape of atom?

Answer 27

spherical

Question 28

relationship between the amount of electricity used in electrolysis and the amount of chemical reaction that occurs

Answer 28

michael faraday

Question 29

oil-drop experiment

Answer 29

robert milikan

Question 30

cathode-ray tube experiment

Answer 30

Joseph jhon Thomson

Question 31

the smallest unit tat retains the properties of an element

Answer 31

atom

Question 32

all matter is composed of atoms and these cannot be made or destroyed

Answer 32

Dalton's theory

Question 33

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

Answer 33

atomic number (A)

Question 34

the number of protons in the nucleus of an atom determines its identity this numbers known as the atomic number of that element

Answer 34

atomic number (Z)

Question 35

they are atoms containing the same number of protons but different numbers of neutrons

Answer 35

isotopes

Question 36

represents the comosition of the nucleus

Answer 36

nuclide symbol