Chemistry Revision

Question 1

Define acid

Answer 1

An acid is a substance that can attack metal clothing or the skin. Has a PH of less than 7. They are proton (H+ ion) donators.

Question 2

Give me the definition of activation energy

Answer 2

Activation energy is the minimum energy needed to start a reaction.

Question 3

Explain Alkali metals

Answer 3

An alkali metal is elements in group 1 of the period table.

Question 4

Give me an example of an alkali metal.

Answer 4

An example is Lithium (Li). Sodium (Na). Potassium (K)

Question 5

Define Alkane

Answer 5

An alkene is a saturated hydrocarbon that has no double bonds between the carbon atoms

Question 6

Give me an example of an alkane.

Answer 6

An example of an alkane is Ethane

Question 7

What does alkene mean?

Answer 7

An alkene is unsaturated hydrocarbon that contains a carbon bond.

Question 8

Explain what alloy means.

Answer 8

An alloy is a mixture of metals (and sometimes non- metals)

Question 9

Give me an example of an alloy

Answer 9

An example is Brass- a mixture of Copper and Zinc.

Question 10

Define Aluminium

Answer 10

Aluminium is a low density corrosion- resistant materials used in many alloys.

Question 11

Explain Anhydrous

Answer 11

Anhydrous describes a substance that does not contain water.

Question 12

What does an aqueous solution mean?

Answer 12

An aqueous solution is a mixture made by adding a soluble substance to water.

Question 13

Define atoms.

Answer 13

Atoms are the smallest part of an element which can be recognised as an element.

Question 14

Explain atomic number.

Answer 14

Atomic number is the number of protons (which equals the number of electrons) in an atom. It is sometimes called the proton.

Question 15

What does atomic weight mean?

Answer 15

Atomic weight is the historical term that was used before relative atomic masses were defined in the 20th century.

Question 16

Define a base.

Answer 16

A base is an oxide, hydroxide or carbonate of a metal that forms a salt as a product when it reacts with acid. They are proton (H+ion) acceptors.

Question 17

Explain biodegradable.

Answer 17

Biodegradable is materials that cane broken down by microorganisms.

Question 18

What does biodiesel mean?

Answer 18

Biodiesel is fuel for cars made from plant oils.

Question 19

Define Biofuel

Answer 19

Biofuel is fuel made from animal or plant products.

Question 20

Give me the meaning of bioleaching

Answer 20

Bioleaching is the process of extraction of metals from ores using microorganisms.

Question 21

Define a blast furnace

Answer 21

A blast furnace is the huge reaction vessels used in industry to extract iron from its ore.

Question 22

What does bond energy mean?

Answer 22

Bond energy is the energy needed to break a particular chemical bond.

Question 23

Define a Burette

Answer 23

A burette is a long glass tube with a tap at one end makings to show volumes of liquid used to add precisely known amounts of solution to a solution in a conical flask below it.

Question 24

Explain Calcium Carbonate

Answer 24

Calcium Carbonate is the main compound found in limestone. It is white solid whose formula is CaCO

Question 25

What does Calcium Hydroxide mean?

Answer 25

Calcium Hydroxide is a white solid made by reacting calcium oxide with water. It is used as a cheap alkali in industry.

Question 26

Define Calcium Oxide

Answer 26

Calcium Oxide is a white solid made by heating limestone strongly. For example in a lime kiln.

Question 27

Explain Carbon Monoxide

Answer 27

Carbon Monoxide is a toxic gas whose formula is CO

Question 28

What does cast iron mean?

Answer 28

Cast Iron is an impure iron taken directly from a blast furnace.

Question 29

Define a Catalyst

Answer 29

A catalyst is a substance that increases the rate of a chemical reaction. It is not used or changed in the reaction.

Question 30

Explain what cement means

Answer 30

Cement is a building material made by heating limestone and clay.

Question 31

Define Chromatography

Answer 31

Chromatography is the process whereby small amounts of dissolved substances are separated by running a solvent along a material such as absorbent paper.

Question 32

What does Collision theory mean?

Answer 32

Collision theory is an explanation of chemical reactions that says particles colliding have to have a sufficient amount of energy in order for a reaction to take place.

Question 33

Define a compound

Answer 33

A compound is a substance made when two or more elements are chemically bonded together. For example water (H20) is a compound made from hydrogen and oxygen.

Question 34

Explain what Concrete means

Answer 34

Concrete is a building material made by mixing cement sand and aggregate (crushed rock) with water.

Question 35

Define convection currents

Answer 35

Conviction currents are the circular motion of matter caused by heating in fluids.

Question 36

Explain a copper- Rich core

Answer 36

A copper Rich- core is a rock that contains a high proportion of a copper compound.

Question 37

Define Core

Answer 37

The core is the centre of the earth

Question 38

Give me the meaning of Covalent Bonding

Answer 38

Covalent bonding is the attraction between two atoms that share one or more pairs of electrons.

Question 39

Define Cracking

Answer 39

Cracking is the reaction used in oil industry to break down large hydrocarbons into smaller more useful ones. This occurs when the hydrocarbon vapour is either passed over a hot catalyst or mixed with steam and heated to a high temperature.

Question 40

What does crust mean?

Answer 40

The crust is the outer solid layer of the Earth.

Question 41

Define Delocalised Electron

Answer 41

Delocalised Electrons is a bonding electron that is no longer associated with any one particular atom.

Question 42

Explain displace

Answer 42

Displace means when one element takes place of another in a compound.

Question 43

Give me the meaning of distillation

Answer 43

Distillation is the separation of a liquid from a mixture by evaporation followed by condensation.

Question 44

Define Dot and Cross Diagram

Answer 44

Dot and Cross diagrams are a drawing to show the arrangement of the outer shell electrons only of the atoms or ions in a substance.