Mole shoit

Question 1

Elements

Answer 1

● All substances are made up of certain element(s).
● An element is a substance that cannot
be broken down into a simpler
substance by chemical means.
● It consists of only one type of atoms
that are chemically combined.

Question 2

Compounds

Answer 2

● A compound is formed from two or more different elements
chemically combined in a fixed ratio.
● Compounds have different properties from the elements that they are
made from.

Question 3

Mixtures

Answer 3

● Mixtures contain more than one element and/or compound that are
not chemically bonded together and so retain their individual
properties.
● Mixtures can be either homogeneous or heterogeneous.

Question 4

homogeneous

Answer 4

A homogeneous mixture has a uniform appearance and composition
throughout (e.g. salt solution, air, alloys)

Question 5

heterogeneous

Answer 5

A heterogeneous mixture consists of visibly different substances or
phases (e.g. sand and water, soil).

Question 6

Macroscopic differences:

Answer 6

○ Shape
○ Volume

Question 7

Microscopic differences:

Answer 7

Arrangement of particles
○ Speed of particles
○ Attraction forces

Question 8

Physical changes

Answer 8

● In a physical change, no new substances are
produced.
● Changes of state are physical changes - such as
melting, boiling, freezing, condensation.

Question 9

sublimation

Answer 9

solid to gas

Question 10

Chemical changes

Answer 10

● A chemical change results in the formation of new chemical substances.
● In a chemical reaction, the atoms in the reactants are rearranged to
form new products.