Unit 1: Chemical Changes and Structure

Question 1

What affects the Rate of Reaction?

Answer 1

Concentration

Particle Size

Temperature

Use of a Catalyst

Question 2

How do you measure the rate of reaction?

Answer 2

Measuring:

• Changes in Mass(At Regular Time Intervals)
• Changes in Volume (At Regular Time Intervals)
• Changes inConcentration (At Regular Time Intervals)

Question 3

What are reactions caused by?

Answer 3

Particles colliding with each other

Question 4

Why does High Temperature affect Reaction Rate?

Answer 4

Particles have more energy and move quicker causing more frequent collisions with more energy

Question 5

Why does Small Particle Size affect Reaction Rate?

Answer 5

Increased surface area means a higher chance of particles colliding

Question 6

Why does High Concentration affect Reaction Rate?

Answer 6

More particles moving means more particle collisions

Question 7

Calculating Rate of Reaction

Answer 7

Average Rate = Change in measurable Quantity/Change in Time

Units depend on measurable quantity and time

Question 8

Reaction Graphs

Answer 8

Steeper Gradient = Faster Reaction

Flat/Straight line = End of Reaction

Question 9

Atoms

Answer 9

Particles that make up everything. Made from protons, neutrons and electrons

Question 10

Electrons

Answer 10

Negatively charged particles that orbit the nucleus. Their mass is so small it is nearly 0

Question 11

Protons

Answer 11

Positively charged particles contained in the nucleus of the atom. Have a mass of 1amu

Question 12

Neutrons

Answer 12

Particled with no charge that are also contained in the nucleus. Have a mass of 1amu

Question 13

Nucleus

Answer 13

Centre of an atom made up from protons and neutrons. Has an overall positivie charge

Question 14

Group 1

Answer 14

Alkali Metals. React rapidly with water, producing an alkaline solution and hydrogen gas

Question 15

Group 0/8

Answer 15

Noble Gases. Very unreactive and exist as individual atoms

Question 16

Atomic Number

Answer 16

How many protons an element has

Question 17

Mass Number

Answer 17

Number of protons and neutrons in an atom

Question 18

Isotopes

Answer 18

Atoms with the same atomic number but different mass numbers

Question 19

Relative Atomic Mass (RAM)

Answer 19

Calclated from the masses of all the isotopes of an element taking into account the percentage proportion of each

Question 20

Covalent Bond

Answer 20

A shared pair of electrons between two non-metal atoms

Question 21

Diatomic Molecules

Answer 21

Bromine

Iodine

Chlorine

Fluorine

Oxygen

Hydrogen

Nitrogen

Question 22

Linear Molecule

Answer 22

One shared electron

Question 23

Bent Molecule

Answer 23

Two shared Electrons

Question 24

Pyramidal Molecule

Answer 24

Three Shared Electrons

Question 25

Tetrahedral Molecule

Answer 25

Four Shared Electrons

Question 26

Ionic Bonding

Answer 26

Formed between a metal and a non-metal. An electrostatic force of attraction between a charged metal ion and an oppositely charged non-metal ion

Question 27

Ionic Compunds

Answer 27

Easily Dissolve in water to form a conductive solution

Very high melting points

Don’t conduct when solid

Solid at room temperature

Question 28

Covalent Network

Answer 28

Very high melting/boiling point

Solid at room temperature

Don’t conduct (except graphite)

Question 29

Electrolysis

Answer 29

The breaking up of an ionic compund using electricity. Charged particles attracted to oppositely charged electrode where they lose/gain electrons to become neutral atoms/molecules

Question 30

Prefixes

Answer 30

Mono - 1

Di - 2

Tri - 3

Tetra - 4

Penta - 5

Hexa - 6

Question 31

Balanced Equations

Answer 31

When there are the same number of the type of every atom on both sides of the equation

Question 32

Mass of One Mole

Answer 32

Gram Formula Mass (GFM)

Question 33

Mole Calculations

Answer 33

Mass(g) = Number of Moles x Gram Formula Mass

m = n x GFM

Question 34

Concentration Calculation

Answer 34

Number of Moles = Concentration (mol l^-1) x Volume (l)

n=cv

Question 35

Acids pH

Answer 35

Less than 7

Question 36

Alkalis pH

Answer 36

More than 7

Question 37

Neutral/Water pH

Answer 37

7

Question 38

Formin Alkalis

Answer 38

Metal Oxide (base) dissolved in Water

Question 39

Forming Acids

Answer 39

Non-Metal Oxide Dissolved in Water

Question 40

When do Acids Occur?

Answer 40

When there are more H⁺ ions than OH^- ions

Question 41

When do Alkalis Occur?

Answer 41

There are more OH^- ions than H⁺ ions

Question 42

When do Neutral Solutions Occur?

Answer 42

There are an equal number of OH^- ions and H⁺ ions

Question 43

Dilution

Answer 43

Moving an acid or alkalis pH towards 7 with water.

Occurs as there is a lower concentration of ions as water is added

Question 44

Neutralisation

Answer 44

Reaction of an acid with a base that results in the pH moving towards 7

Question 45

Neutralisation Equations

Answer 45

Acid + Alkali → Salt + Water

Acid + Metal Oxide → Salt + Water

Question 46

Neutralisation with Carbonates

Answer 46

H⁺ ion reacts with CO₃^2- to form water and carbon dioxide

Question 47

Metal Carbonate Neutralisation Equation

Answer 47

Metal Carbonate + Acid → Salt + Water + Carbon Dioxide

Question 48

Carbon Dioxide Test

Answer 48

Tuns lime water milky/chalky white

Question 49

Formation of Water

Answer 49

Hydrogen ion and Hydroxide ion combine to form water

H⁺_(aq) + OH^-_(aq) → H₂O_(l)

Question 50

Titration

Answer 50

Used to find the concentration of an Acid/Alkali

Question 51

Base

Answer 51

Substance that reacts with an acid forming water