Physical vs. Chemical Properties
What type of property can be measured without changing the chemical identity of a material?
Physical property
What is the density of pure liquid water?
1.0g/cm3 (or 1.0g/mL)
What is a pure substance made of only one type of atom?
An element
What happens to particle speed when thermal energy is added?
Particle speed increases
What engineering term means giving up one feature to gain a different advantage?
A trade-off
Adding acid to limestone produces gas bubbles. What type of property was tested?
Chemical property (reactivity)
What is the formula for calculating density?
Density=Mass / Volume
What is a pure substance made of two or more different elements chemically combined?
A compound
What form of energy is associated with particle motion?
Kinetic energy
What does a life-cycle diagram show about a drink container?
Inputs, outputs, manufacturing steps, and disposal/recycling impacts.
Is bending a metal strip a physical or chemical property?
Physical property (the metal's chemical identity does not change)
Pine wood has a density of 0.6g/cm3. Will it sink or float in water?
Float (its density is less than 1.0g/cm3)
How does a simple molecule differ from an extended structure?
Simple molecules have a fixed number of atoms; extended structures form repeating grid networks.
Describe the particle movement inside a solid.
Particles vibrate in fixed, tightly packed positions.
Why might a company's advertisement contain bias?
It highlights positive features while hiding negative features or environmental impacts.
Name two physical properties that help identify an unknown metal without reacting to it.
Density and malleability (or color / state)
In a column of three mixed liquids, where does the highest-density liquid settle?
The very bottom layer
Name one substance that forms a 3D extended lattice in its solid state.
Table salt (NaCl) or Diamond (C)
Why did the soap bubble expand when heated in our lab?
Air particles gained thermal energy, moved faster, and pushed outward.
Give one advantage of using aluminum over glass for drink cans.
Aluminum is lighter to ship and does not shatter easily.
Why can't scientists rely on color alone to identify an unknown element?
Many different elements share the exact same color.
A block has a mass of 30g and a volume of 6cm3. What is its density?
5.0g/cm3 (It sinks)
Why are extended structures usually solids at room temperature?
They have continuous networks of strong chemical bonds throughout the structure.
What happens to particle spacing when a solid melts into a liquid?
Particles break out of fixed positions and slide past each other.
How can you tell if a claim about a material in an advertisement is based on scientific evidence rather than opinion?
It uses data and facts from tests rather than personal feelings or judgments.