Matter & Pure Substances
What two things must something have to be considered matter?
Mass and volume (takes up space)
What type of mixture has the same composition throughout?
Homogeneous mixture
Does a liquid have a definite or indefinite shape and volume?
Indefinite shape, definite volume
Is flammability a physical property or a chemical property?
Chemical property
What is the formula for calculating density?
Density = Mass ÷ Volume
Air, steel, and nitrogen are examples of substances. Which one is an element?
Nitrogen
Sand mixed with water is an example of which type of mixture?
Heterogeneous mixture
What phase change occurs when a gas becomes a liquid?
Condensation
Iron can be attracted to a magnet. Is magnetism a physical or chemical property?
Physical property
What method can measure the volume of an irregularly shaped solid by placing it in water?
Water displacement
Is distilled water an element, compound, or mixture?
Compound
Air is a uniform mixture of gases. Is it a solution, colloid, or suspension?
Solution
What is the name of the physical change when a solid changes directly into a gas?
Sublimation
A piece of iron is cut in half. Is this a physical or chemical change?
Physical change
A wooden block has a mass of 40 g and a volume of 50 mL. What is its density?
0.8 g/mL
What is the difference between a compound and a mixture?
A compound contains elements chemically combined in a fixed ratio; a mixture contains substances physically combined.
A mixture scatters light but its particles do not settle to the bottom. What type of mixture is it?
Colloid
Nitrogen melts at −210°C and boils at −196°C. What state is nitrogen in at −200°C?
Liquid
An iron rod is cut into two pieces and later begins to rust. Identify which event is a physical change and which is a chemical change.
Cutting: physical change. Rusting: chemical change.
Iron has a density of 8 g/cm³. What is the mass of a piece of iron with a volume of 40 cm³?
320 g
Classify table salt (NaCl) and lemonade as either pure substances or mixtures.
Table salt: pure substance (compound). Lemonade: mixture.
A cloudy brown liquid separates over time, leaving solid particles at the bottom. The particles can also be removed using filter paper. What type of mixture is it?
Heterogeneous mixture — suspension
Four substances have these melting points: hydrogen −259°C, nitrogen −210°C, hydrogen sulfide −85°C, and sulfur dioxide −73°C. Which would be the last to freeze as they are cooled from the liquid state?
Hydrogen (lowest freezing point)
Potassium iodide and lead(II) nitrate solutions are mixed, producing a bright yellow solid. Name two observations indicating that a chemical reaction occurred.
Color change and formation of a precipitate
A liquid has a mass of 58.5 g and a volume of 50 mL. Is it water (1.00 g/mL), oil (0.84 g/mL), or sugarwater (1.17 g/mL)?
Sugarwater (1.17 g/mL).