How do you define a pure substance? What are the two kinds of pure substances?
Matter that contains only 1 kind of atom or 1 kind of molecule. Elements and Compounds.
What is a solution?
Homogeneous mixture where one substance is dissolved in another.
Particles are not visible. Cannot be filtered. Particles do not settle. No Tyndall Effect.
What technique would you use to separate: Pure water from salt water
Simple distillation (evaporate the water but need to condense the water to collect it)
What is a physical property? What is a chemical property?
Physical Property: a property of a substance that can be observed without changing its identity
Chemical Property: a property of a substance that can be observed or measured as it interacts with other substances
What does SI stand for? What country developed this system?
System International. France.
How do you define an elements? How do you define a compound?
Pure substance that only contains one kind of atom.
Pure substance that only contains one kind of molecule.
What is a solute? What is a solvent?
Solute is the substance present in the least amount. (gets dissolved)
Solvent is the substance present in the largest amount. (dissolving medium)
What technique would you use to separate: Iron from a mixture of dirt and iron filings
Magnetism (Iron has the physical property of being magnetic)
What is a physical change? What is a chemical change?
Physical change: A change where no new substances are produced; matter’s identity stays the same although it may look different.
Chemical change: A change where new substances are produced
Which of these units are apart of the SI System?
meter, inch, gram, second, ounce, gallons, Kelvin, foot, kilogram, pound, centimeter, liter, Degrees Fahrenheit
Meter, Gram, Second, Kelvin, Kilogram, Centimeter, Liter
How do you define a mixture?
Matter that is made of 2 or more different substances that are physically bonded together, rather than chemically bonded.
Define unsaturated solution. Define saturated solution. Define supersaturated solution.
Unsaturated: A solution containing less solute than can actually be dissolved in the solvent
Saturated: A solution containing as much solute as the solvent is capable of dissolving
Supersaturated: A solution containing more solute than the solvent can hold at room temperature
Describe the process of chromatography.
A separation techniques based on the physical property solubility.
There is a stationary phase and mobile phase. The paper is placed in a solvent. The solvent runs up the paper and pulls the different substances up the paper depending on how soluble each substance is.
If it runs further up the paper, the more soluble that substance is. If it doesn't run far up the paper, the less soluble that substance is.
Is this an example of a physical or chemical change?
Food is digested in the stomach to release its nutrients
Chemical change
What is the metric conversion scale (From K to m). Tell me the name and the symbol.
Kilo (k), Hecto (h), Deka (da), BASE UNIT, Deci (d), Centi (c), Milli (m)
How do you define heterogenous mixture? How do you define homogenous mixture?
Heterogenous Mixture is a mixture where you can see the different components. Homogenous Mixture is a mixture where you cannot see the different components.
What is a colloid? What is a suspension?
Colloid: Homogenous mixture (no particles visible). Cannot be filtered. Particles do not settle. Yes Tyndall Effect.
Suspension: Heterogenous mixture (particles visible). Can be filtered. Particles do settle. Yes Tyndall Effect.
What's the difference between simple distillation and fractional distillation?
Fractional distillation has the fractionating column which causes other substances that evaporated too early to condense back into the original mixture.
Simple distillation is for separating one liquid from a dissolved solid or from another liquid. Fractional distillation is for separating multiple liquids from one another.
Is this an example of a physical or chemical property?
Copper is an excellent thermal and electrical conductor.
Physical Property
Complete this conversion: 24.67 hm = ___________ cm
You need to show me the complete conversion factor with ALL units.
24.67 hm = 246,700 cm
24.67 hm x (10,000 cm / 1 hm) = ____ cm
What is a diatomic element?
Element that made of 2 atoms of that kind of element (same kind of atom)
Label these 3 examples are either a solution, colloid, or suspension: paint, salt water, and muddy water. Provide some reasoning.
Solution: salt water (homogenous, no Tyndall Effect)
Colloid: paint (homogenous, yes Tyndall Effect)
Suspension: muddy water (heterogenous, yes Tyndall Effect)
Why can mixtures be separated? Give an example of this kind of property.
They can be separated based on physical properties because no chemical reaction occurs when its mixed. One example: physical property - solubility
Is this an example of a physical or chemical change?
Your breath becomes visible when you breathe out in the cold air.
Physical Change
Complete this mathematical operation. Round your answer to the appropriate number of sig. figs.
(5.12 + 70.589) x (98.4 - 40.00)
(75.709) x (58.40) = 4,421.4056...
Original Value Sig Figs: 3, 5, 3, 4
Rounded Answer to 3 Sig Figs: 4,420