1. Chapter 3 Ultimate Review!
Mrs. DiGennaro
Chem 1A

2. Quantitative vs. Qualitative
Quantitative = QUANTITY = NUMBERS (It is 39 degrees Celsius)
Qualitative = QUALITY = NO NUMBERS (it is hot)
You try it: Describe your shoes qualitatively and quanitatively

3. Scientific Notation Move the decimal behind the first non-zero digit
Count the number of ‘jumps’
Jump right? Negative exponent
Jump left? Positive exponent
You try it:
3,123,901.22

4. Accuracy/Precision/Error
Accuracy: How close your values are to the ‘true value’
Precision: How close your measurements are to each other.
Error: ‘How wrong were you?’ … This is the (absolute value of) difference between your value and the accepted value (difference means SUBTRACT)
Percent Error: IErrorI/accepted value x 100
You try it!
Elizabeth performed an experiment and found that water boiled at 98 degrees celsius. What is the percent error of her data? What could have caused this error?

5. Significant figures KNOW THE RULES!
Every non-zero digit is significant= 1,234 has 4 significant figures
Zeros between non-zero digits are significant = 1001 has 4 significant figures
Leftmost zeros before a nonzero digit are NOT significant = has 2 significant figures
Zeros at the end of a number AND to the right of a decimal point ARE significant has 5 significant figures
Zeros at the end with no decimal point are NOT significant = 1,000,000 has 1 significant figure
When adding/subtracting, line up decimal point and round your answer to the least number of DECIMAL places in the problem = = 4.2 (The answer has 1 decimal place because that is the lowest number of decimal places)
When Multiplying/dividing, round your answer to the least number of significant figures

6. SI system of Measurement
Length = meter
Volume = cubic meter
Mass = kilogram*
Temperature = kelvin*
Time = second
*Why do you think the SI unit is kilogram and not gram? Kelvin and not celsius?

7. Convert!!! mega (M) 1,000,000 times larger than the unit
kilo (k) 1,000 times larger than the unit
deci (d) 1/10 the size of the unit
cent (c) 1/100 the size of the unit
milli (m) 1/1000 the size of the unit
micro ( ) 1/1,000,000 the size of the unit

8. Density Density= relationship between and objects mass and volume
Density = mass/volume
You try it: What is the density of a copper penny that has a mass of 3.1 grams and a volume of 0.35 cubic centimeters? What is your unit?

9. Temperature Temperature shows us the heat transfer
Feels cold to you? Heat going to that object
Feels hot to you? Heat going from object to you
Temperature scales
Celsius = based on freezing point (0 degrees) and boiling point (100 degrees) of water
Kelvin = based on ABSOLUTE ZERO
K = Degrees Celsius + 273
Degrees Celsius = K – 273
You try it! At what temperature (kelvin) does water boil? At what temperature (kelvin) does water freeze?

10. What type of questions will you see?
Conversion questions. For example, how many grams in 27.4 kilograms?
Significant figures
Count them, round to a specific significant figure, add/subtract/multiply/divide
Write in scientific notation
Is it accurate? Precise? What is the percent error?
Be able to solve for the missing value in a density problem
Temperature conversion: kelvin-Celsius and reverse