Phys or Chem
It All Matters
All Mixed Up!
More or Less Dense
Anything goes...
100
The classification of the following change as physical or chemical:
H2O(l) -> H2O(g)
What is physical?
100
All matter can be classified as…
(two categories)
What is Pure Substances or Mixtures ?
100
Two categories of mixtures. Explain the difference between them.
What is Heterogeneous and Homogeneous ?
Heterogeneous mixtures are those that DON'T dissolve (a difference between the substances can be seen) and a homogeneous mixtures are those that dissolve (it all looks the same).
100
The density formula.
What is d=m/V ?
100
State the name: Mg
What is Magnesium
200
Then density of magnesium.
(Hint: Table S)
What is 1.74 g/cm3?
200
Matter that is considered to be pure can be classified as…
What is elements or compounds ?
200
State one technique that could be used to separate sand and water. Describe the results.
What is filtration ?
The sand will be collected on the filter and the water will go through it.
200
A substance that's less dense than corn oil.
What is isopropanol, mineral oil or ethanol?
200
State the symbol: silver
What is Ag?
300
Two observations that would indicate a chemical change took place.
What is fire, gas production (bubbles), sudden color change, forming a precipitate?
300
A sample of matter composed of two or more different elements that are chemically combined in a fixed ratio.
What is a compound ?
300
State one technique that could be used to separate salt and water. Describe the results.
What is evaporation (boiling) or distillation ?
The water will evaporate, leaving the salt behind.
300
A student argues that the density of water is 1.0 g/mL, independently of the amount of water that is used to calculate it. Is the student correct? Provide evidence.
The student is correct! A sample of water with a mass of 5 grams would have a volume of 5 mL, making the density 1 g/mL. A larger sample of water with a mass of 100 g would have a volume of 100 mL, making the density 1 g/mL. Density is a constant value for a given substance.
300
Classify it: CO2(aq)
What is a homogeneous mixture ?
400
Which sample of matter can be separated into different substances by physical means?
- LiCl dissolved in water (aq)
- LiCl as a solid (s)
- NH3 as a liquid (l)
- NH3 as a gas (g)
What is (1) LiCl dissolved in water (aq) ?
400
Define “solution”
What is a a homogeneous mixture ?
400
This is what happens if you add water to a solid mixture of salt and sand.
What is the salt will dissolve in the water but the sand will not?
400
"The density of dishwashing liquid is 1.10 g/ml."
Could this statement be true? Explain.
Yes! The density of dishwashing liquid is higher than the density of water because it is below water on the density column.
400
Classify it: Oil and Vinegar
What is Heterogeneous mixture ?
500
A student observes water boiling. She states that the change must be chemical because she could see rapid bubbling. Is the student correct? Explain your answer.
What is... Not correct. Phase changes are always physical changes.
500
State one specific way in which compounds and homogeneous mixtures are different.
What is compounds are chemically combined and mixtures are physically combined ?
500
A separation technique that separates substances with different boiling points.
What is distillation?
500
An unknown sample has a mass of 3.9g and a volume of 1.5 mL. Calculate the density, including the units and correct mathematical setup.
What is d = 3.9g / 1.5 mL ?
d = 2.6 g/mL
500
Separate it: Color ink
What is chromatography ?