Study Tips
- start early
- read previous labs
- answer any questions you missed
- all numbers have units
- don't repeat units in a table
- correct sig. dig.
Physical and Chemical Change
Signs of chemical change
- colour change
- odour emitted
- temperature change
- bubbles form in liquid
- precipitate forms in liquid
- difficult to reverse
- light emitted
A chemical change means that new particles formed
A physical change means that particles stayed the same.
Observations
- Only record what you see, hear, smell, touch.
- Clarity: transparent, translucent, opaque
- Colour: colourless
Classifying Matter
- Pure substance: only one kind of particle --> element, compound
- Mixture: two or more types of particles --> solution, homogeneous, heterogenous, mechanical
Lab Safety
- You can lose marks if you are being unsafe.
Charging Objects
Law of Electric Charges
+ and – attract
+ and + repel
– and – repel
Ways to charge things
- friction: rub two materials together
- induction: bring a charged object near a neutral object, without touching (temporary or permanent)
- conduction: a charged object touches a neutral object
- grounding: a charged object touch a large reservoir of charges and becomes neutral.
Electrostatic Series
- a list of materials
- must compare two at a time
- material on top is more likely to lose electrons
Electroscopes
- to find the charge on an object
- Pith ball: tells you if object is neutral or charged
- Metal leaf: tells you if object is neutral or charged
- use a rod that has a known charge to determine if object is positive or negative.
Homework:
P. 137 - 138 (Bioamplification)
P. 52 (Tolerance Ranges)
Example of a dry lab:
- What is the optimal temperature to grow this plant?
- At what temperatures would the plant die?
- Describe how the plant would grow at 10° C.
- Based on this data, what areas in the world would you expect to find this plant?
No comments:
Post a Comment