Gr9 Chem Exam Review

Question 1

What are the states of matter and properties?

Answer 1

Solid - fixed shape, most attraction between particles, do not take shape of container,

Liquid - takes shape of container, less attraction, flows

Gas - least attraction between particles, takes shape

Question 2

Changes of state

Answer 2

1. melting - S-L
2. evaportaion -L-G
3. depotition - G-S
   (these three add heat)
4. solidification - L-S
5. sublimation - S-G
6. Condensation - G-L
   (these 3 take away heat)

Question 3

Physical properties

Answer 3

Lustre - shiny vs dull

Density - d=m/v

Colour - the colour

Conductivity - conducts heat and electricity, opp to is insulator

Ductility - pull into wire

Hardness - resist being scratched
opp is brittle

Malleabillity - bend but won’t break

Viscosity - ability to flow

Question 4

Chemical properties

Answer 4

• ability to change into new sub
• how it reacts with other sub
• observed with chemical change
  ex - absurds heat
• reacts with acid
• reacts with O2

Question 5

Physical Change

Answer 5

• change of state
• change of shape
• dissolving
  ex crushing stone
  melting chocolate

Question 6

Chemical change

Answer 6

• colour change
• odour
• gas formed
• heat/light formed
• precipitate
• new sub
• non reversible
  ex toast-colour and odour change

Question 7

What is an ion, isotope, ionic isotope, atom

Answer 7

Ion- charge
Isotope- change in mass
Ionic isotope- charge and change in mass
Atom- nothing changes

Question 8

Importance of valence electrons

Answer 8

• bonding/stability
• outer most electrons
• column #

Na (one dot above). Cl (7 dots)

                     LEWIS DOT

Question 9

Properties of ionic compounds

Answer 9

• metal +non metal
• tranfers electrons
• high boiling point
• dissolves into H2O
• high melting point

Question 10

Properties of covalent compounds

Answer 10

• non mental + non metal
• shares electrons
• low boiling point
• most don’t dissolve into H2O
• low melting point

Question 11

Properties of metals

Answer 11

• left of periodic table
• loses electrons and becomes a cation (positive)
• solid, shiny, malleuble

Question 12

Properties of non metals

Answer 12

• right side of periodic table
• gains electrons and becomes negative anion
• brittle
• gases

Question 13

Properties of a metaloid

Answer 13

• stair case
• properties of metal and non metals

Question 14

Formulas for density, mass and volume

Answer 14

d=m/v
m=dxv
v=m/d