1.1 Qualitative and Quantitative Analysis

Name 5 physical properties

1. Colour

2. Odour

3. Taste

4. State

5. Hardness

Define physical state

• The form in which matter exists at various temperatures

Define the three physical states that matter can exist in

1. Solid

2. Liquid

3. Gas

Describe the states of gold, mercury, helium at room temperature

• Gold: solid

• Mercury: liquid

• Helium: gas

Define density

• The amount of mass of a substance in a given volume

In terms of density, why is lead used as a fishing weight?

• Because lead is denser than water

Describe density in terms of two equal volume fishbowls each with a different amount of marbles inside

• If one fishbowl contains more matter (more marbles) then this object is considered to be more dense

Define malleability

• The ability to be compressed or pounded into a thin sheet without shattering

What classic object is a perfect example for malleability?

• Aluminum → it can be hammered into sheets of aluminum foil!

Define ductility

• The ability to be stretched or drawn into the shape of a thread, strand, wire

What is the opposite of ductility?

• Brittle

What is a classic example of ductility?

• Candy taffy → can be drawn into thin strands

Define thermal conductivity

• The ability to transfer heat to something else

What is a good example of thermal conductivity?

• Metal for pots and pans → metal is effective at conducting heat from the burner the food

Define electrical conductivity

• The ability for a substance to conduct electricity

What is a good example of something with good electrical conductivity?

• Copper → like wires in cables

Define solubility

• The ability of one substance to dissolve another

Define solute and solvent

• Solute is what dissolves

• Solvent is what does the dissolving

Describe solute and solvent using water and salt

• Salt is the solute because it is being dissolved

• Water is the solvent because it is dissolving the salt

“Each chemical will typically change from one state of matter to another at a-”

• “-specific temperature”

When does water change from liquid ← → solid?

• At 0^oC

When does water change from liquid ← → gas?

• At 100^oC

Define sublimation

• Transition of a substance directly from a solid to a gas completely skipping liquid phase

Define deposition

• Transition of a substance directly from a gas to a solid completely skipping liquid phase

“A solid _____ to a liquid and _____ to gas”

• “Melts”

• “Vaporizes”

“A gas _____ to a liquid and _____ to a solid”

• “Condenses”

• “Freezes”

Changes of state are considered to be physical properties because why? Use water as an example

• Because no new chemical is actually made

• Liquid water, ice, steam are all H₂O

• The chemical simply exists in different states

Matter can be classified based on its ability to react which means what?

• Changing into a new substance with different properties

Define combustibility. Give an example

• Ease or difficulty with which a substance burns

• Gasoline is combustible

Define reactivity with acids. Give an example

• Ease or difficulty with which a substance reacts with acids

• Baking soda with vinegar (acid)

Define reactivity with water. Give an example

• Ease or difficulty with which a substance reacts with water

• Sodium (or potassium) reacts with water

Define qualitative analysis

• Compare qualities you observe to a predetermined sample or patter

Define quantitative analysis

• Uses techniques that measure the quantity of a particular substance

• Produces numbers with units like %, g, L

Describe qualitative and quantitative analysis for an unknown sample

• Qualitative: determine what substances are present

• Quantitative: quantify how much of each substance in found

What happens if you place an unopened can of both regular and diet soda into a lake?

• Regular: denser than water so it sinks. Why? Because it has a lot of dissolved sugar which increases the mass

• Diet: less dense so floated. Does not have dissolved sugar.

• Both cans have the same amount of liquid (volume) but the regular is made out of a liquid that has a higher mass