cp chemistry chapter 3

CP ChemistryChapter 3

Test review

Qualitative and quantitative measurements

• Ben is taller than Jerry

• Ben is taller than Jerry, who is 6’1”

• Ben is 6’3” tall

Accuracy and precision

• What do a group of numbers look like which are precise but not accurate?

• If a group of numbers are accurate, are they precise?

Significant figures in measurements

• .00047• 74000• 7007• 74000.• 74.00• .007400• What are the rules for addition?• What are the rules for multiplication?

Rounding

• .00753 3 sig figs• .00753 2 sig figs• .00753 1 sig fig

• Remember that we round in order to observe the significant figures in calculations!!

• Do the calculation, then round the number

Scientific notation

• .000000747• 7470000000• 7.47• .0747

• Remember, when we make one side larger, we make the other side smaller

Error and percent error

• What is error• What is percent error

SI system

• The SI units for :

• Length• Mass• Time• Temperature

Prefixes

• Milli• Kilo• Centi• Mega

• What is .05 centimeter in meters?

Liters and cubic centimeters

• What is 1 milliliter?• What is the mass of a liter of water?

• 1 liter of water is 1 kilogram• 1 cm3 = 1 g of water (@4°C)

1 liter1 kilogram

10 cm

Weight vs mass

• Mass is a property of matter

• Weight is a consequence of mass and gravity and can depend on location

Temperature

• Degrees centigrade• Kelvins

• Conversion ??

Volume calculations

• Volume of rectangular solids• Volume of cylinders

Density

• Formula for density?• How do we calculate mass?• What about volume?

Specific gravity

• What is it?• What do we use it for?