Bell-ringer: Draw This Triangle

1. An object has a mass of 468 g and a volume of 15 cm3. What is its density?

2. The density of an unknown mass is 3.5 g / cm3. It has a volume of 30 cm3. What is its mass?

3. The density of an unknown mass is 6.8 g / cm3. Its mass is

47 g. What is its volume?

Physical versus Chemical Properties

Chapter 5

• Matter: anything that has mass and takes up space– Mass – the amount of matter in something– Volume – the amount of space something

occupies

• Which of the following is matter?– A car?– A box?– You?

Reviewing MATTER

What is a property?

• Property: a characteristic of a substance that can be observed

Physical Property

Physical property: a property that can be observed using your senses without changing the identity of the substance.

Examples:

• luster (shine)

• malleability: the ability to be hammered into a thin sheet

• ductility: the ability to be stretched into a wire

• melting point

• boiling point

• density

• solubility (how well it dissolves in water)

Special Physical Properties

• Melting point: the temperature at which a substance changes from a solid to a liquid at a given pressure

water = 0oC

• Boiling point: the temperature at which a substance changes from a liquid to a gas at a given pressure

water = 100oC

Chemical Properties

• Chemical property: a property that can only be observed by changing the identity of the substance. These properties usually describes how something reacts.

Examples:

•flammability

•ability to rust

•reactivity with vinegar

**These properties are hard to observe**

Density

• Density is the amount of mass per unit of volume.

• Density can be used to identify a substance.

• The density of water is 1.0g/mL

Calculate the Density (Use your Triangles)

• 1. A gold-colored ring has a mass of 18.9 grams and a volume of 1.12 mL. Is the ring pure gold? (The density of gold is 19.3 g/mL.)

• 2. What volume would a 0.871 gram sample of air occupy if the density of air is 1.29 g/L?

• 3. Pumice is volcanic rock that contains many trapped air bubbles. A 225 gram sample occupied 236.6 mL. What is the density of pumice? Will the pumice float on water?

Calculate the Density

4. A cup of sugar has a volume of 237 mL. What is the mass of the cup of sugar if the density is 1.59 g/mL?

• 5. Which has the greater mass, 1 liter of water or l liter of gasoline? The density of water is 1.00 g/mL and that of gasoline is appoximately 0.68 g/mL.

• 6. A crumpet recipe calls for 175 grams of flour. According to Julia Child's data, the density of flour is 0.620 g/mL. How many mL of flour are needed for this recipe?

Physical or Chemical

• 1. ( Physical or Chemical ) properties describe matter. •  • 2. ( Physical or Chemical ) properties of a substance can be easily observed.• • 3. One can use their five senses to determine the ( Physical or Chemical )

properties of a substance. • • 4. ( Physical or Chemical ) properties usually describe how a substance reacts.•  • 5. ( Physical or Chemical ) properties are not as easy to observe.• • 6. ( Physical or Chemical ) properties can be used to identify substances.

Physical or Chemical

• 7. Oxygen is odorless and colorless

•

• 8. Copper turns green when exposed to the environment

•

• 9. The piece of metal is magnetic

•

• 10. The density of water is 1.0 gram per cubic centimeter

•

• 11. Diamonds are a very hard substance

•

• 12. The tree is 8 meters high

•

• 13. Sodium reacts very easily with other elements.

• 14. Copper conducts electricity

•

• 15. Water is a liquid

•

• 16. The mass of the NaCl sample is 30 grams

•

• 17. Gold is nonflammable

•

• 18. Alka-Seltzer tablets react with water to produce gas

•

• 19. The color of the ball is red

• Matching Identify if the following are chemical or physical properties:

Physical or Chemical

• 20. Iron reacts with oxygen and forms rust

•

• 21. The boiling point of water is 100 degrees C

•

• 22. Baking soda reacts with vinegar

•

• 23. The gas is flammable

•

• 24. Oxygen is a gas

• 25. Argon is not very reactive

•

• 26. Nitrogen is a colorless gas

•

• 27. The silver spoons tarnished and turned dark

•

• 28. The piece of metal is magnetic

•

• 29. A student’s shirt suddenly bursts into flames.

•

• 30. Silver necklaces tarnish and turn green.

Draw this pH Scale

Properties of Acids

• Taste sour

• Corrosive (react with metals)

• Produce color changes with indicators

• Blue litmus paper turns red

Examples of common acids

• Acetic acid= vinegar

Acids

• Citric acid= citrus fruits

Acids

• Acetylsalicylic acid= aspirin

Acids

• Ascorbic acid= vitamin C

Acids

• Carbonic acid= carbonation

Acids

• Hydrochloric acid= stomach juices

Acids

• Sulfuric acid= car batteries

Properties of Bases

• Bitter taste

• Slippery to touch

• Red litmus paper turns blue

Examples of common bases

• Ammonia= household cleaner, fertilizer, production of nylon

Bases

• Aluminum hydroxide= deodorant, laxatives

Bases

• Sodium hydroxide= drain cleaner, soap making