demos for this lecture 1 kg mass (is it heavy?) 50 ml of alcohol and 50ml of water in graduated...
TRANSCRIPT
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