Semester 1: Chemistry

Question 1

atom

Answer 1

the smallest particle of a chemical element that can exist.

Question 2

element

Answer 2

are composed of all types of atoms and have specific chemical properties.

Question 3

atomic number

Answer 3

number of protons
=number of electrons

Question 4

Mass number

Answer 4

neutrons and atom

Question 5

isotopes

Answer 5

different atoms are same element if they have same amount of protons

Question 6

groups

Answer 6

go down
have similar chemical properties
same number of electrons in the outershell

Question 7

periods

Answer 7

go across
have same number of electron shells being filled
have same physical properties

Question 8

transition metals

Answer 8

have similar physical properties and can fro, different ions, have similar chemical properties

Question 9

Core charge

Answer 9

the attractive force of the nucleus and valence electrons
no. of protons - no. of inner electrons
down a group remains consistent
left to right increase due to valence electrons more attracted to nucleus

Question 10

atomic radius

Answer 10

a measurement of the size of atoms. It is the distance from the nucleus to the valence shell electrons.
gets bigger going down and smaller as you go across
bigger because shells are added
decreased across because increasing nuclear charge

Question 11

lowest energy electron shells

Answer 11

closest to nucleus, they fill first

Question 12

Orbital shells

Answer 12

s:2
p:6
d:10
f:14

Question 13

ion

Answer 13

An ion is an atom or group of atoms that has a
positive or negative charge.
Nonmetals tend to form anions.
Metals tend to form cations.

Question 14

Why are elements in the periodic table arranged in order of atomic number rather than relative atomic mass?

Answer 14

No two elements can have the same atomic number\Atoms are listed in the periodic table in order of atomic number because the atomic number determines the number of electrons, and this in turn sets the properties that make each element unique. Relative atomic mass does not relate directly to either the atomic number or the electron number.

Question 15

Explain the relationship between electronegativity and core charge.

Answer 15

The greater the core charge of an atom, the greater the electronegativity.

Question 16

electronegativity

Answer 16

the ability of an atom to attract electrons in a molecule.
down a group decreases valence electrons are less strongly attracted to the nucleus
valence electrons are more attracted to nucleus so increases

Question 17

metals

Answer 17

Reactivity of metals increases down a group
Reactivity of metals decreases across a period

Question 18

non metals

Answer 18

decreases going down
increases acrosses period

Question 19

metallic bonding

Answer 19

These electrons are called delocalised electrons. The electrostatic force of attraction between the negatively charged delocalised electrons and the positively charged metal cations holds the structure together.

Question 20

Metallic bonding properties

Answer 20

high melting and boiling point
mallueable
ductile

Question 21

spoon to hot to hold

Answer 21

The delocalised electrons in the metal spoon obtain energy from the boiling mixture and move quickly. These electrons move freely throughout the spoon, colliding with other electrons and metal ions, transferring energy so that the spoon becomes warmer and, eventually too hot to hold

Question 22

copper conducts elctricity

Answer 22

When a current is applied to the copper wire, the delocalised electrons (free moving electrons) move from one end to the other and so the copper wire conducts electricity

Question 23

ionic compound

Answer 23

An ionic compound is formed when a metal atom donates one or more electrons to a non-metal.

Question 24

electrovalency

Answer 24

The charge on an ion is known as its electrovalency.

Question 25

ionic structure

Answer 25

Ionic compounds are poor conductors of heat and electricity as solids, as there are no free charged particles that can transfer the charge.

Question 26

Covalent bonding

Answer 26

Nonmetal + nonmetal
Sharing of electrons
have low melting and boiling points
be liquid, gas, or soft solids at room temperature

Question 27

alkanes

Answer 27

single bond 2n+2

Question 28

alkenes

Answer 28

double bond 2n

Question 29

alkynes

Answer 29

triple bond 2n-2

Question 30

ionisation

Answer 30

Ionisation energy is the least amount of energy needed to remove an electron from an atom or ion in the gas phase.

Question 31

AB → A + B

Answer 31

decompisition

Question 32

General: A + B → AB

Answer 32

synthesis

Question 33

AB + C → AC + B

Answer 33

single displacement

Question 34

AB(aq) + CD(aq) → AD(s) + CB(aq)
water and one solid

Answer 34

double displacement or precipitate

Question 35

AB + CD → AD + CB

Answer 35

double displacement

Question 36

CH4(aq) + 2O2(aq) → CO2(aq)+ 2H2O(l

Answer 36

combustion

Question 37

HA(aq) + BOH(aq) →AB(aq)+ H20(l

Answer 37

acid base neutralisation
OH evident

Question 38

electrostatic attraction

Answer 38

attractive or repulsive forces between particles that are caused by their electric charges

Question 39

Monatomic

Answer 39

only one atom in molecule

Question 40

Lattice

Answer 40

3d strucuture