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Question 1

What is a physical change

Answer 1

an alter in appearance that can be easily reversed, doesn’t change the substance

Question 2

What is a chemical change

Answer 2

Product is different from reactant, usually heat, gas, or bubbling produced or some some color change

Question 3

Examples of physical change

Answer 3

Melting, freezing, boiling, and condensing

Question 4

Examples of chemical change

Answer 4

combustion, decomposition, e.t.c

Question 5

Definition of Atom

Answer 5

the smallest unit of matter that has properties of a chemical element

Question 6

Definition of molecule

Answer 6

2 or more atoms covalently bonded together

Question 7

Definition of compound

Answer 7

2 or more atoms chemically bonded

Question 8

Definition of element

Answer 8

It’s made from 1 type of atom that can’t be be broken down further

Question 9

Defintion of mixture

Answer 9

2 or more atoms that aren’t chemically bonded

Question 10

What is a metal

Answer 10

On the left side of the periodic table, good conductors and lusturous

Question 11

What is a non metal

Answer 11

On the right side of the periodic table, can’t conduct heat or electricity

Question 12

What is paper chromatography

Answer 12

a technique used for the separation of compounds based on the differential solubility in the stationary phase and mobile phase (solvent).

Question 13

How to create a paper chromatography investigation

Answer 13

Draw a pencil line on a piece of chromatography paper then place the solution on the line. Use a pencil to label, then pour solvent into a beaker place paper into beaker paper should be dipped but pencil line above. Then wait until solvent nearly reaches top of paper. Draw a line there.

Question 14

Why do you use a pencil in paper chromatohraphy

Answer 14

Ink may travel with the solvent up the paper

Question 15

How to obtain a dry sample from a chromatography paper

Answer 15

Cut that bit off and evaporate the sample

Question 16

What is the R^f values

Answer 16

the ratio of how far the substance travelled in comparison to the solvent

Question 17

What is the importance of purity

Answer 17

Control of purity is important for accuracy thus effective research and the safety of consumer usage.

Question 18

What temperature does water boil or freeze

Answer 18

100 degrees to boil, 0 to freeze

Question 19

What happens if x is impure

Answer 19

it will boil or freeze over a range of temperatures

Question 20

What happens if a substance becomes impure

Answer 20

Impurities in a liquid can raise its boiling point and lower freezing point

Question 21

When to use filtration

Answer 21

Separating solids from liquids:

Question 22

How to do filtration

Answer 22

Pour your mixture down a filter funnel with filter paper, the ppt. should stay and solvent is in the conical flask.

Question 23

When to do crystallisation

Answer 23

Purifying solids: Crystallization is ideal for purifying solids from a solution, such as purifying sugar or salt from a solution.
separate different solubilities, su
Purifying liquids: Crystallization can purify liquids by removing impurities that are insoluble in the solution, such as removing impurities from a solution of sugar.

Question 24

How to do crystallisation

Answer 24

Heating the solution: Heat the solution to a temperature where the impurities are soluble, but the desired substance is not.
Cooling the solution: Allow the solution to cool slowly, allowing the desired substance to crystallize out of the solution.
Collecting the crystals: Collect the crystals by filtration or centrifugation, and wash them with a solvent to remove any remaining impurities.

Question 25

When to do distillation

Answer 25

Distillation is ideal for separating a mixture of liquids with significantly different boiling points.

Question 26

How to do distillation

Answer 26

Set up the distillation flask, condenser, and collection flask Add the mixture to be distilled to the distillation flask. Apply heat to the distillation flask using a Bunsen burner, . Monitor the temperature using a thermometer. Vaporize the mixture: Heat the mixture until it reaches its boiling point, producing vapor. The vapor rises into the condenser. The condenser cools the vapor, causing it to condense back into a liquid. This liquid is the distilled product. The distilled product is collected in the collection flask or receiver.

Question 27

When to do fractional distillation

Answer 27

When there are minor differences in the boiling point of the two liquids

Question 28

How to do fractional distillation

Answer 28

Same setup as distillation but use a fractionating collum so only the liquid with the lowest boiling point can be condensed into the other conical flask

Question 29

What is law of conservation of mass

Answer 29

the mass of any one element at the beginning of a reaction will equal the mass of that element at the end of the reaction.

Question 30

What is air

Answer 30

a mixture of compounds, elements, and molecules

Question 31

What is the liebig condensor

Answer 31

A condensing equipment where there are two valves the first one where cold water exits and the second one where cold water enters.