Chemistry

Question 1

What is an Element

Answer 1

Elements are made up of one type of atom.

Question 2

What is a Compound?

Answer 2

They have more than one type of atom which cannot easily be separated. Example H20 (Water)

Question 3

What is a mixture?

Answer 3

A mixture is made up of one or more substances but not chemically joined

Question 4

ELEMENT, COMPOUND or MIXTURE

What is Silver?

Answer 4

ELEMENT

Question 5

Is it elenment, compound or mixture

What is Water

Answer 5

Compound

Question 6

Is it an element, compound or mixture?

What is Oxygen?

Answer 6

Compound

Question 7

Is it an element, compound or mixture?

What is Salt (Sodium Chloride)?

Answer 7

Compound

Question 8

Is it an element, compound or mixture?

What is sea water?

Answer 8

mixture

Question 9

Is it an element, compound or mixture?

What is carbon dioxide

Answer 9

compound

Question 10

Is it an element, compound or mixture?

What is Nitrogen?

Answer 10

element

Question 12

Is it an element, compound or mixture?

What is air?

Answer 12

mixture

Question 13

Define freezing?

Answer 13

it is the change of state of a liquid to a solid

Question 14

Define condensing

Answer 14

This is the process of moving a gas to a liquid

Question 15

Define sublimation

Answer 15

turning a solid into a gas

Question 16

Meling ice is a physcal reaction - what is a physical reaction?

Answer 16

This is the process of changing a state change from say liquid to gas, water to steam.

Question 17

Meling ice is a physcal reaction, can you give another example?

Question 18

Define what the boiling point is

Answer 18

This is the temp that a elelment will start to change state from a liquid to a gas.

Question 19

Define the the term ‘melting point’

Answer 19

This is the temp that an element will start to turn from a solid to a liquid.

Question 20

What is a pure substance?

Answer 20

They contain a single element or compound with no other substance.

They wiil have a defined melting and boiling point.

Question 21

What is an impurity in a substance?

Answer 21

This is where an otherwise pure substance has small amounts of other substances.

Question 22

If you have an impure substance, will they have a defined melting and boiling point?

Answer 22

No, impure substances could boil or melt at different tempraters/.

Question 23

How can you separate a mixture?

Answer 23

filtation
evapourartion
simple distilliation
paper chromatography

Question 24

What does soluable mean?

Answer 24

This means that a solid can disolve in a liquid

Example Salt in Water

Question 25

What does insoluable mean?

Answer 25

This means that a solid cannot disolve in a liquid. | Example Sand in water

Question 26

What is a solute?

Answer 26

The solid disovled into a liquid is called a solute.The solute and solvent create a solution. | Salt is the solute when it is disovled into water and the solution is sa

Question 27

What is a solvent?

Answer 27

This is the liquid that a solid has been disolved into. The solute and solvent create a solution. | Water is the solvent when salt is disolved into it and the solution is s

Question 28

How could I separate sand from water? What apparatus do I need? What would the sand and water be called once separated?

Answer 28

Sand is insoluable. Filteration can be used. A filter funnel and filter paper would be used, The sand is left in the filter paper and is called residue. The liquid in the filter funnel is called the residue.

Question 29

# Example salty water How could I separate a solution? How does this work?

Answer 29

Evapouration could be used An evapourating dish and Bunsern buner is used The salter water is heated and the water will evapourate when boilded to leave behine the salt - which is called the residue.

Question 30

# Copper sulfate cystrals from copper sulfate solution Evapouration is one way to separate a solution can you name another? how does this work?

Answer 30

Crystalisation You heat the mixture to boiling As it cools someof the solute crystalisaises and then evapouration can be used to remove the remaing of the liquid.

Question 31

What is disitliation? What do you use?

Answer 31

Disitliation can be used to separate a solvent from a solution. Liebig Condenser, a round bottom glass and a bunser burner. The mixture is heated until it boils and the vapour passes through the condenser where it cools and becomes a liquid again. It works because the two liquids have two different boiling points,

Question 32

How does paper chromatography work?

Answer 32

Is used to separate mixtures of substances dissolved in solvent. For example different cloured ink or dyes. Draw a 1cm line at bottom of the paper put a small spot of each substance on the line - label place paper in a beaker with small amount of solvent Leave for a few mins - so solvent can travel up paper when solvent near the top take it out and mark the level the solvent reached this is called the solvent front. Leave to dry this is called the chromatram.

Question 33

For each Gas Solid Liquid Are the particals arranged closely together?

Answer 33

Gas - No Solid - Yes Liquid - Yes

Question 34

For each Gas Solid Liquid Are the particals able to move freely?

Answer 34

Gas - Yes Solid - No Liquid - Yes

Question 35

For each Gas Solid Liquid Are the particals a fixed shape?

Answer 35

Gas - No Solid - Yes Liqid - No

Question 36

For each Gas Solid Liquid Are the particals fixed volume?

Answer 36

Gas - No Solid - Yes Liquid - Yes

Question 37

For each Gas Solid Liquid Are the particals can be compressed?

Answer 37

Gas - Yes Solid - No Liquid - ?

Question 38

What needs to be added to a solid to change it a liquid?

Answer 38

Heat needs to be added to add energy to the solid. This moves it to its melting point.

Question 39

What must all the atoms of an element be? ## Footnote The periodic table, atomic structure and bonding

Answer 39

The same type of atom

Question 40

What are atoms made up of?

Answer 40

protons, electrons and neutrons

Question 41

What is contained in the neculeus of an atom?

Answer 41

The protons and neutrons

Question 42

In an atom how are the electrons arranged?

Answer 42

Electrons are arranged in an electron shell around the nuclues made up of protons and neutrons

Question 43

How is the mass of an atom calcualted?

Answer 43

This is the some of the mass of the elections, protons and neutrons that the atom is made up of. The mass of the electrons does not impact the mass of an atom - the main particals are the protons and neutrons.

Question 44

Does an atom have a postitive charge?

Answer 44

No as a proton has a + 1, neutrons have 0, electrons have -1 charge and there are always the same number of electrons and neutrons making all atoms netural.

Question 45

Does an atom have a negative charge?

Answer 45

No as a proton has a + 1, neutrons have 0, electrons have -1 charge and there are always the same number of electrons and neutrons making all atoms netural.