SI units International System of Units SI Units

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SI units International System of Units

SI units International System of Units

SI Units Base Units Time – second (s) Length – meter (m) Mass –

SI Units Base Units Time – second (s) Length – meter (m) Mass – kilogram (kg) Temperature – Kelvin (K) Amount of a substance – mole (mol) Electric Current – ampere (A) Luminous intensity – candela (cd)

SI Units Derived Units Volume – cubic decimeter (dm 3) or liter (L) Density

SI Units Derived Units Volume – cubic decimeter (dm 3) or liter (L) Density – kilograms/Liters (kg/L) In chemistry we will use grams/milliliter (g/m. L or g/cm 3) There are many more derived units

Metric Prefixes Larger than the base unit Mega (M) means 1, 000 1 x

Metric Prefixes Larger than the base unit Mega (M) means 1, 000 1 x 106 g = 1 Mg Kilo (k) means 1, 000 1 x 103 L = 1 k. L Hecto (h) means 100 1 x 102 m = 1 hm Deca (da) means 10 1 x 101 g = 1 dag

Metric Prefixes Smaller than the base unit deci (d) means 1/10 1 g =

Metric Prefixes Smaller than the base unit deci (d) means 1/10 1 g = 1 x 101 dg centi (c) means 1/100 1 L = 1 x 102 c. L milli (m) means 1/1, 000 1 m = 1 x 103 mm

Metric Prefixes Smaller than the base unit micro ( ) means 1/1, 000 1

Metric Prefixes Smaller than the base unit micro ( ) means 1/1, 000 1 g = 1 x 106 g nano (n) 1 L = 1 x 109 n. L means 1/1, 000, 000 Angstrom (Å) 1 m = 1 x 1010 Å means 1/10, 000, 000

Dimensional Analysis or the Factor Label Method 1 step problem Example – How many

Dimensional Analysis or the Factor Label Method 1 step problem Example – How many grams are in 3. 42 kg? 1. Write down your known 3. 42 kg

1 Step Problem Example – How many grams are in 3. 42 kg? 2.

1 Step Problem Example – How many grams are in 3. 42 kg? 2. Write down the conversion that involves your known unit on bottom and the unit you want to go to on top. 3. 42 kg x 1000 g 1 kg

1 Step Problem 3. Cancel out units and solve. Remember if you have the

1 Step Problem 3. Cancel out units and solve. Remember if you have the same unit on top and on bottom, they cancel out. 3. 42 kg x 1000 g 1 kg = 3420 g

Practice How many Liters are in 1. 5 x 106 n. L? 1. 5

Practice How many Liters are in 1. 5 x 106 n. L? 1. 5 x 106 n. L x 1 L 1 x 109 n. L = 1. 5 x 10 -3 L

Practice How many milligrams are in 260 grams? 260 g x 1000 mg 1

Practice How many milligrams are in 260 grams? 260 g x 1000 mg 1 g = 260, 000 mg

2 Step problem Example – How many milligrams are in 3. 42 kg? 1.

2 Step problem Example – How many milligrams are in 3. 42 kg? 1. Map out your strategy. Write the unit you are starting with, the base unit you are going to, and the unit you want to end with. kg g mg Start base final

2 Step problem Example – How many milligrams are in 3. 42 kg? 2.

2 Step problem Example – How many milligrams are in 3. 42 kg? 2. Write down your known 3. 42 kg

2 Step Problem 3. Write down the first conversion. Remember, the conversion that involves

2 Step Problem 3. Write down the first conversion. Remember, the conversion that involves your known unit on bottom and the base unit on top. 3. 42 kg x 1000 g = 1 kg

2 Step Problem 4 a. Add the second conversion. Remember, the conversion that involves

2 Step Problem 4 a. Add the second conversion. Remember, the conversion that involves your known unit on bottom and the base unit you want to go to on top. 3. 42 kg x 1000 g x 1 kg

2 Step Problem 4 b. Add the second conversion. Remember, the conversion that involves

2 Step Problem 4 b. Add the second conversion. Remember, the conversion that involves your base unit on bottom and the unit you want to go to on top. 3. 42 kg x 1000 mg = 1 kg 1 g

2 Step Problem 5. Cancel out units and solve. Remember if you have the

2 Step Problem 5. Cancel out units and solve. Remember if you have the same unit on top and on bottom, they cancel out. 3. 42 kg x 1000 mg 1 kg 1 g = 3. 42 x 106 mg

Practice How many milligrams are in 260 kilograms? kg g mg 260 kg x

Practice How many milligrams are in 260 kilograms? kg g mg 260 kg x 1000 mg 1 kg 1 g = 2. 6 x 108 mg

Practice How many megameters are in 50. Angstroms? Å m Mm 50 Å x

Practice How many megameters are in 50. Angstroms? Å m Mm 50 Å x 1 m x 1 Mm 1 x 1010Å 1 x 106 m = 5 x 10 -15 Mm

English to Metric Prefixes Length 2. 54 cm = 1 in Mass 454 g

English to Metric Prefixes Length 2. 54 cm = 1 in Mass 454 g = 1 lb Volume 1 L = 1. 06 qt

Multiple Step problem Some English to Metric Calculations will have multiple steps. Ex. How

Multiple Step problem Some English to Metric Calculations will have multiple steps. Ex. How many ft are in 240 nm? 1. Map out your strategy. Write the unit you are starting with, the bridge between the two systems, and the unit you want to end with. nm m cm in ft Start base bridge finish

Multiple Step problem Some English to Metric Calculations will have multiple steps. Ex. How

Multiple Step problem Some English to Metric Calculations will have multiple steps. Ex. How many ft are in 240 nm? 2. Fill in any missing conversions.

Multiple Step problem Example – How many ft are in 240 nm? 1. Write

Multiple Step problem Example – How many ft are in 240 nm? 1. Write down your known 240 nm

Multiple Step Problem 2. Write down the first conversion. Remember, the conversion that involves

Multiple Step Problem 2. Write down the first conversion. Remember, the conversion that involves your known unit on bottom and the base unit on top. 240 nm x 1 m = 1 x 109 nm

Multiple Step Problem 3. Add the other conversions. 240 nm x 100 cm x

Multiple Step Problem 3. Add the other conversions. 240 nm x 100 cm x 1 in x 1 ft = 1 x 109 nm 1 m 2. 54 cm 12 in

Multiple Step Problem 4. Cancel out units and solve. Remember if you have the

Multiple Step Problem 4. Cancel out units and solve. Remember if you have the same unit on top and on bottom, they cancel out. Your final answer should have the same amount of sig figs as the number you started with. 240 nm x 100 cm x 1 in x 1 ft = 1 x 109 nm 1 m 2. 54 cm 12 in = 7. 9 x 10 -7 ft

Practice How many milligrams are in 12 ounces? oz lb g mg 12 oz

Practice How many milligrams are in 12 ounces? oz lb g mg 12 oz x 1 lb x 454 g x 16 oz 1 lb 1000 mg 1 g = 3. 4 x 105 mg

Practice How many miles are in 17. 0 km? km m cm in ft

Practice How many miles are in 17. 0 km? km m cm in ft mi 17. 0 km x 1000 m x 100 cm x 1 in___ x 1 ft x 1 mi__ 1 km 1 m 2. 54 cm 12 in 5280 ft = 10. 6 mi

Density = Mass/Volume d = m/v m = dv v = m/d

Density = Mass/Volume d = m/v m = dv v = m/d

Density Example: What is density of an object with a mass of 10. 0

Density Example: What is density of an object with a mass of 10. 0 g and a volume of 2. 0 cm 3? 1. Write down your knowns on the left and your formula on the right.

Density Example: What is density of an object with a mass of 10. 0

Density Example: What is density of an object with a mass of 10. 0 g and a volume of 2. 0 cm 3? Knowns M = 10. 0 g V = 2. 0 cm 3 D=? Formula d = m/v

Density 2. Plug in and solve. Include units on all numbers.

Density 2. Plug in and solve. Include units on all numbers.

Density Example: What is density of an object with a mass of 10. 0

Density Example: What is density of an object with a mass of 10. 0 g and a volume of 2. 0 cm 3? Knowns M = 10. 0 g V = 2. 0 cm 3 D=? Formula d = m/v D = 10. 0 g / 2. 0 cm 3 = 5. 0 g/cm 3

Density Example: What is the mass of an object with a density of 4.

Density Example: What is the mass of an object with a density of 4. 0 g/m. L and a volume of 0. 5 m. L? Knowns Formula m=? m = dv v = 0. 5 m. L d = 4. 0 g/m. L m = 4. 0 g/m. L x 0. 5 m. L =2 g

Density Example: What is the volume of an object with a density of 4.

Density Example: What is the volume of an object with a density of 4. 0 g/m. L and a mass of 0. 5 g? Knowns Formula m = 0. 5 g v = m/d v=? d = 4. 0 g/m. L v= 0. 5 g / 4. 0 g/m. L = 0. 125 m. L = 0. 1 m. L

Area Length x width Ex. What is the area of a piece of paper

Area Length x width Ex. What is the area of a piece of paper 18. 0 cm x 22. 0 cm?

Volume Length x width x height Ex. What is the volume of a wood

Volume Length x width x height Ex. What is the volume of a wood of paper 27. 0 cm x 14. 0 cm x 8. 0 cm?

Converting between units with Area and Volume Ex. What is the area of a

Converting between units with Area and Volume Ex. What is the area of a piece of paper 7. 0 cm x 9. 0 cm? What is the area in meters?

Ex. What is the area of a piece of paper 7. 0 cm x

Ex. What is the area of a piece of paper 7. 0 cm x 9. 0 cm? What is the area in feet?

Ex. What is the volume of a piece of metal 57. 0 mm x

Ex. What is the volume of a piece of metal 57. 0 mm x 9. 0 mm x 12 mm? What is the volume in kilometers?

Ex. What is the volume of a piece of metal 57. 0 mm x

Ex. What is the volume of a piece of metal 57. 0 mm x 9. 0 mm x 12 mm? What is the volume in kiloliters?