Atomic Theory

Question 1

what is chemistry?

Answer 1

the study of matter

-matter is anything with mass or volume

Question 2

what is an element?

Answer 2

pure substance made up of one type of atom

-cannot be broken down

Question 3

what is a compound?

Answer 3

pure substance made up of two or more elements

-can be broken down

Question 4

what are subatomic particles?

Answer 4

particles that make up an atom

Question 5

location of electron plus basic info (charge, relative mass)?

Answer 5

shells surround the nucleas

• charge: negative one (-1)
• mass: 1

Question 6

location of proton plus basic info (charge, relative mass)?

Answer 6

nucleus

• charge: positive one (+1)
• mass: 1836

Question 7

location of neutron plus basic info (charge, relative mass)?

Answer 7

nucleus

• charge: neutral (0)
• mass: 1837

Question 8

why is nucleus positively charged overall?

Answer 8

neutrons have no charge

Question 9

what occupies the most volume in an atom?

Answer 9

electrons

Question 10

what is a neutral atom?

Answer 10

protons and electrons are the same

Question 11

what is an ion?

Answer 11

a charged atom/atom has lost of gained electrons to become a electrically charged particle
-does not have equal amount of protons and electrons

Question 12

what is the atomic number?

Answer 12

number of protons in nucleus

Question 13

what is the mass number?

Answer 13

sum of protons and neutrons in nucleus

• mass of atom comes mostly from p and n bc electrons almost have no weight
• is whole number

Question 14

what is an isotope?

Answer 14

atoms with different number of neutrons (protons are the same)

Question 15

what is the atomic mass?

Answer 15

average mass of all atoms in an element

• different isotopes of atoms exist resulting in different weights of atoms
• is decimal number

Question 16

how to find mass number?

Answer 16

number of protons + number of neutrons

Question 17

who invented the periodic table?

Answer 17

dmitri mendeleev

Question 18

where are the metals found on the pt?

Answer 18

left side

Question 19

where are the non-metals found on the pt?

Answer 19

right side

Question 20

what are the elements along the staircase called?

Answer 20

metalloids

Question 21

what are horizontal rows of the pt called?

Answer 21

periods

Question 22

what are vertical rows of the pt called?

Answer 22

families/groups

Question 23

alkali metals info:

• side and group
• reactive level
• examples

Answer 23

left side group 1
highly reactive
lithium, sodium, potassium

Question 24

alkaline earth metals info:

• side and group
• reactive level
• examples

Answer 24

left side group 2
somewhat reactive but not as much as alkali metals
beryllium, magnesium, calcium

Question 25

halogen non metals info: - side and group - reactive level - examples

Answer 25

right side group 17 very reactive flourine, chlorine, bromium, iodine

Question 26

noble gases info: - side and group - reactive level - examples

Answer 26

right side group 18 highly non reactive six noble gases: helium, argon, krypton, xenon, neon, radon

Question 27

what happens when atoms lose or gain electrons?

Answer 27

they become ions

Question 28

what happens to an atom that loses electrons and which atoms will lose electrons?

Answer 28

- becomes positively charged | - all metals lose electrons

Question 29

what happens to an atom that gains electrons and which atoms will gain electrons?

Answer 29

- becomes negatively charged | - all non metals gain electrons

Question 30

what group will not form ions?

Answer 30

noble gases

Question 31

what are multivalent metals?

Answer 31

metals that can form ions in multiple ways depending on the chemical reaction they undergo

Question 32

how to find number of electrons?

Answer 32

protons - charge

Question 33

how to find number of neutrons?

Answer 33

mass number - protons

Question 34

how to find mass number?

Answer 34

protons + neutrons

Question 35

what is a charge of 0?

Answer 35

neutral atom

Question 36

what is positive/negative charge?

Answer 36

ion

Question 37

how many electrons can the first shell hold?

Answer 37

2

Question 38

how many electrons can the second shell hold?

Answer 38

8

Question 39

how many electrons can the third shell hold?

Answer 39

8

Question 40

what does the period number represent?

Answer 40

number of occupied shells of atom

Question 41

what do the elements in the same family have in common?

Answer 41

same number of electrons on outermost shell

Question 42

what is the valence shell and electrons?

Answer 42

outermost shell and electrons in that shell

Question 43

what happens when you move left to right across a period?

Answer 43

one electron is added to the valence shell

Question 44

what is a full set of eight electrons called?

Answer 44

stable octet

Question 45

what happens when you change the number of protons?

Answer 45

new element created

Question 46

what happens when you change the number of neutrons?

Answer 46

different isotope created

Question 47

what happens when you change the number of electrons?

Answer 47

ion is produce

Question 48

why do other elements try to imitate noble gases?

Answer 48

noble gases are stable and have stable octet (full valence shells)

Question 49

how to other elements imitate nobles gases?

Answer 49

by losing or gaining electrons from other atoms in chemical reactions

Question 50

what happens when a metal meets a non metal?

Answer 50

they exchange electrons and have opposite charges that attract

Question 51

what is an atom?

Answer 51

smallest particle of an element that retains the property of that element