IQ1

Question 1

Chemical Change (Reaction)

Answer 1

A chemical change is the breaking and remaking atomic bonds to form a new product. It is irreversible.
Examples: Combustion, Decomposition.
Signs: Gas is produced, temperature changes, colour changes, light is given, precipitate is produced.

Question 2

Physical change

Answer 2

Physical properties change to create a new shape/form of the same product. No new product and change is reversible.
E.g Change of state, mixing/ dissolving.

Question 3

Chemical properties

Answer 3

Describes how one substance reacts with other substances to form new ones e.g Flammability, acidity, reactivity.

Question 4

Physical properties

Answer 4

Characteristics of a substance that can be observed or measured before changing it chemical composition.
E.g Colour, density, melting/boiling point.

Question 5

Homo/Heterogenous

Answer 5

Homo= same all the way through
Hetero= Different

Question 6

Magnetism

Answer 6

Magnetic field which arise from the motion of electric charges.

Question 7

Particle size

Answer 7

Affects several properties of a substance, inclduding its reactivity, solubility and how it behaves in different environments.

Question 8

Melting/Boiling point

Answer 8

Temperature where solid becomes a liquid than temperature when liquid becomes a gas

Question 9

Density

Answer 9

How much mass is packed into a given volume

Question 10

Electrical conducivity

Answer 10

Degree to which a material conducts electricity.

Question 11

Thermal conductivity

Answer 11

How easily heat can pass through a substance.

Question 12

Viscocity

Answer 12

How easily a liquid flows

Question 13

Accuracy

Answer 13

how close your experiments are to the true value. How accurate is your equipment e.g 3 decimal place scales

Question 14

Reliability

Answer 14

how consistent are your results when the test is repeated

Question 15

Validity

Answer 15

does your experiment test what it is supposed to test