Density

Density• Density is how

compact matter is.• More mass shoved

into a certain amount of space makes something more dense.

Density Considers Two Things

Density Considers Two Things

• How much mass is present.

Density Considers Two Things

• How much mass is present.

• How much volume does it take up.

Density Considers Two Things

• How much mass is present.

• How much volume does it take up.

• Make sure consider both these factors when discussing density.

Answer questions 1,2,4and 5

1. What does Figure A illustrate about density?

2. What does Figure B illustrate about density?

3. If the cube of aluminum in figure B were cut into four equal parts. How would the density of one part compare to the whole cube?

4. Metals expand when heated. If the gold cube in part B is heated, what will happen to its density?

Does it Float?• If something floats or

rises it is less dense than the material it is floating/rising in.

• Objects of greater density will sink.

Density• Density is the mass per unit volume.

Density• Density is the mass per unit volume.

• Density = Mass ÷ Volume

Density• Density is the mass per unit volume.

• D = Mass ÷ Volume

÷

Solving For Variables

Common Volume Units

Illegal ivory is often detected on the basis of density. What is the density of the elephant tusk?

Mass = 2680g

Volume = 1450cm3

Illegal ivory is often detected on the basis of density. What is the density of the elephant tusk?

Mass = 2680g

Volume = 1450cm3

D = 2680g ÷ 1450cm3 = 1.8482g/cm3 = 1.85g/cm3

Calcium chloride is used as a deicer on roads in winter. Its density is 2.50g/cm3. What mass of calcium chloride will the truck hold if its volume is 4560L?

Calcium chloride is used as a deicer on roads in winter. Its density is 2.50g/cm3. What mass of calcium chloride will the truck hold if its volume is 4560L?

4560L = 4,560,000cm3

Calcium chloride is used as a deicer on roads in winter. Its density is 2.50g/cm3. What mass of calcium chloride will the truck hold if its volume is 4560L?

4560L = 4,560,000cm3

M = D x V = 2.50g/cm3 x 4,560,000cm3 = 11,400,000g

The density of methanol is 0.788g/cm3.

What is the minimum volume of a tank that can hold 795kg of methanol.

The density of methanol is 0.788g/cm3. What is the minimum volume of a tank that can hold 795kg of methanol.

795kg = 795,000g

The density of methanol is 0.788g/cm3. What is the minimum volume of a tank that can hold 795kg of methanol.

795kg = 795,000g

795,000g ÷ 0.788g/cm3 = 1,008,883cm3 = 1,010,000cm3

The density of methanol is 0.788g/cm3. What is the minimum volume of a tank that can hold 795kg of methanol.

795kg = 795,000g

795,000g ÷ 0.788g/cm3 = 1,008,883cm3 = 1,010,000cm3

= 1010L

Homework

• Worksheet: Chapter 2-3