chapter 3 (exploring diversity of matter through chemical properties)

Question 1

distinguish among solute, solvent, solution

Answer 1

1) solute - substance that dissolves in a solvent ( e.g salt in water)
2) solvent - substance that dissolves the solute ( water dissolves salt)
< what affects the rate of dissolving >
the temperature (higher temp. = faster)
size of solute particles ( smaller size = larger SA = faster)
rate of stirring ( fast rate of stirring = faster dissolve)
< what affects the solubility >
nature of solvent (diff solvent, diff solubility)
nature of solute (diff solute, diff solubility)
temp. (higher temp. = more solute gets dissolved)

3) solution
- formed when solute dissolves in solvent
- clear
- no solute settles at the bottom ( it all dissolves in the solvent)
- no residue collected if filtered

Question 2

show an understanding that solutions and suspensions are mixtures

Answer 2

3) solution
- formed when solute dissolves in solvent
- clear
- no solute settles at the bottom ( it all dissolves in the solvent)
- no residue collected if filtered
4) suspension
- cloudy
- solute settles at the bottom when left to stand
- residue collected when filtered

• made up of two or more different substances (elements/compounds) not chemically combined
• have the same properties of the substances it is made up of
• can be mixed in any proportion
• no chemical reactions occur and no energy change
• can be separated using physical methods

Question 3

classify elements as metals and non metals based of their properties

Answer 3

non-metals

• poor conductors of heat and electricity
• low melting and boiling points [not incl. carbon & silicon]
• brittle [easily breaks] if solid
• are gases or volatile liquids at room temperature [not inclu. carbon]
• dull

metals

• good conductors of heat and electricity
• shiny
• solid at room temperature [not inclu. mercury]
• malleable [thin sheets], sonorous [sound], ductile [wires]
• high melting and boiling points [not inclu. sodium, potassium, mercury]