We're the Grade 11s in Mr. Doktor's chemistry 11 class.
We're in Block A, Day 1.
We are
Theresa Nguyen
Dominika Skibicki
Charles Perea
Tim Pang
This is our blog.

THE NATURE OF MATTER
WHAT IS MATTER?

• Anything that has mass + takes up space
• Matter can exist in many different states, the most common are

• Solid, Liquid, Gas
• Plasma, Aqueous, Amorphous

· SOLIDS: Holds one shape + has definite volume

· LIQUIDS: Can change shape, but has definite volume

· GAS: Can change shape + volume


CHANGES OF MATTER

· Matter may undergo many changes

· Nearly all changes can be broken down into 3 categories

• Physical Changes
• Chemical Changes
• Nuclear Changes

PHYSICAL CHANGES
· Involves changing shape or state of matter

EX: crushing, tearing, etc.

· No new substances are formed

EX: boiling water, cutting wood, smashing cars

• New substances are formed
• Properties of the matter change

• Conductivity, Acidity, Colour etc.

EX: Iron rusting, burning wood, digesting food

CONSERVATION OF MATTER
· In physical + chemical changes, matter is neither created nor destroyed.

This is called Conservation of Matter

DAY 1B - 09/23/09
On this day we had our chapter test which included questions on precent error, unit conversions, lab safety, and significant digits.

DAY 1D - 09/17/09

That day we had a lab to do. We were to record in an amount of water we had to mix salt. We had to record in a fixed amount of water, how much salt was needed for salt crystals to appear.The purpose of the lab was to find out how much sodium chloride (salt) would dissolve in 10, 20, 30, and 40 mL of water. the group started off by gathering all the essential materials and then filling up water into a graduated cylinder and transferring 10 mL of water into a 50 mL beaker.


DAY 1C - 09/15/09

Expressing Errors

1. Error is a fundamental part of science
2. There are usually 3 reasons for error

• Physical errors in the measuring device
• "Sloppy" Measuring
• Changing ambient conditions

3. Error is taken to be half the smallest division on your measuring device

Calculated Errors

1. 2 Different Possibilities

Absolute Error

• Measured value minus accepted value

ABSOLUTE ERROR = MEASURED - ACCEPTED

• Positive number means you're over the accepted value
• Negative number means you're under the accepted value

Percent Error

• Most common
• Percent error = Absolute Error/Accepted Value

% ERROR = (MEASURED - ACCEPTED/ACCEPTED) x 100
= (OBSERVED - THEORETICAL/THEORETICAL) x 100

Ex: You measure the weight of an orange to be 15 N. The actual weight is 17.5 N. What is the percent error?

• % ERROR = (MEASURED - ACCEPTED/ACCEPTED) x 100
• = (15 - 17.5/17.5) x 100
• = - 14.28
• = 14
  

* ABSOLUTE = I DON'T CARE IF IT'S (-) or (+) *

Dimensional Analysis

• Want to know what 100 km/h is in miles/hr?
• Just like converting between currencies in chem it is usually necessary to convert between unites
• This process is called DIMENSIONAL ANALYSIS

Steps:
There are only 4 steps

1. Find a unit equality
2. Find the conversion factors
3. Apply conversion factors
4. Cancel units

Ex: How many miles are equal to 120 km?
1m = 1.6 km 1 = 1m/1.6 km (120 km)(1 m/1.6 km)
use conversion factor to cancel units

DAY 1B - 09/11/09
Measurement + Chemistry

• In the scientific method accurate measurements are essential

• The most common system in use today is the SI system
• The METRIC SYSTEM started about 300 years ago in France

7 Fundamental Units

• Mass (kg)
• Distance (m)
• Time (s)
• Temperature (K)
• Amount (mol) > 6.02 * 10^23
• Current (A)
• Luminosity (cd)

Significant Digits

1. Digits 1 - 9 are always significant
2. Zeros are significant if they are right of a decimal

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