Atoms and Ions

Question 1

Atom

Answer 1

building block of matter

Question 2

Protons

Answer 2

subatomic particle that is positively charged

Question 3

Electrons

Answer 3

subatomic particle that is negatively charged

Question 4

Neutrons

Answer 4

subatomic particle with no charge that stabilizes the nucleus of an atom

Question 5

Nucleus

Answer 5

central structure containing protons and electrons

Question 6

Atomic number

Answer 6

number of protons

Question 7

Atomic mass

Answer 7

number of protons + neutrons (not electrons because they are practically weightless)

Question 8

Element

Answer 8

chemical substances that cannot be broken down into simpler substances

Question 9

Monoatomic elements

Answer 9

elements stable as single atoms (noble gases)

Question 10

Molecule

Answer 10

substance made of more than one of the same type of atom

Question 11

Molecular elements

Answer 11

pure substances composed of more than one atom of the same element (non-metals)

Question 12

Compound

Answer 12

substance containing different types of atoms in fixed ratios

Question 13

Molecular compound

Answer 13

compound where at least one element has more than one atom of its kind

Question 14

Isotopes

Answer 14

atoms that have the same number of protons but different number of neutrons so they have a different mass e.g Hydrogen 3 (number indicates atomic mass)

Question 15

Shells

Answer 15

a shell contains electrons in the Bohr configuration

Question 16

Max number of electrons in a shell formula

Answer 16

2n^2 (n being number of the shell)

Question 17

Valence shell

Answer 17

outermost shell

Question 18

Valence electrons

Answer 18

number of outermost electrons

Question 19

Octet rule

Answer 19

atoms prefer to have 8 valance electrons. Special octet rule for 3rd shell – 3rd shell has 8 electrons -> the next 2 electrons go to the 4th shell -> electrons continue to fill 3rd shell to maximum of 18 electrons e.g iron has 26 electrons so it is 2, 8, 14, 2

Question 20

Ground state

Answer 20

the energy an atom usually occupies

Question 21

Excited state

Answer 21

temporary instability because when electrons absorb energy, they jump to higher energy shells

Question 22

Groups

Answer 22

columns on the periodic table have the same number of valence electrons thus having similar chemical and physical properties

Question 23

Periods

Answer 23

rows on the periodic table have the same number of occupied shells have the same energy levels

Question 24

Transition metals

Answer 24

elements that can lose different amount of electrons because they have different amounts of valence electrons

Question 25

Ion

Answer 25

elemental atom that has more or less electrons than its neutral atom

Question 26

Cation

Answer 26

positively charged ion (loses electrons). Metals: parent atom + ‘ion’ e.g sodium atom -> sodium ion

Question 27

Anion

Answer 27

negatively charged ion (gains electrons). Non-metals: replace end of parent atom’s name with -ide + ‘ion’ e.g chlorine atom -> chloride ion

Question 28

Ionic bond

Answer 28

electrostatic attraction following a transfer of electrons from a metal to a non-metal

Question 28

Polyatomic ion

Answer 28

a group of atoms that overall has a charge

Question 29

How to express chemical symbols

Answer 29

The first letter is always uppercase
If there is a second letter, it is lowercase
Mass number is protons + neutrons
Atomic number is the no. of protons + no. of electrons
Always integers
Amount of protons = electrons