Density
What is the formula for density?
D = Mass ÷ Volume
What is the definition of a physical property?
A characteristic that can be observed or measured without changing the substance.
Cutting a piece of paper — physical or chemical change?
Physical
What are the 3 main states of matter found on Earth? (AND DRAW the particles!!!)
Solid, liquid, gas
What is the melting point of water?
0°C
What are the units for density of a solid and a liquid?
Solid: g/cm³; Liquid: g/mL
What is the definition of a chemical property?
A characteristic that describes a substance’s ability to change into a new substance.
Burning wood — physical or chemical change?
Chemical
Which state of matter has a definite shape and definite volume?
Solid
What is the boiling point of water?
100°C
If an object’s density is less than water, what will it do?
Float
Give 3 examples of physical properties.
Conductivity, density, state of matter, solubility, magnetism, & Malleability
List one clue that a chemical change has occurred.
Color change, gas production, temperature change, new substance formed, light or sound.
Which phase change turns a liquid into a gas?
Vaporization (boiling/evaporation)
What phase change occurs at the condensation point?
Gas to a Liquid
If a block of metal has a mass of 45 g and a volume of 15 cm³, what is its density?
3 g/cm³
Give 3 examples of chemical properties.
Flammability, reactivity, oxidation, Toxicity, and pH
True or False: Physical changes create new substances.
False
During melting, are particles moving faster or slower?
Faster — energy is added.
During which types of phase changes is energy absorbed (endothermic) and during which is energy released (exothermic)?
Endothermic (energy absorbed): melting, vaporization, sublimation.
Exothermic (energy released): freezing, condensation, deposition.
A rock has a mass of 80 g and a volume of 40 cm³. Calculate its density and determine whether it will float or sink in water. (Include the Density of Water)
Density = 2 g/cm³ → It will sink because the density of the rock is greater than the density of water at 1.0 g/mL
A student tests a metal and observes it reacts with acid and produces gas bubbles. Is that a physical or chemical property? Explain.
Chemical — it describes how the substance reacts and changes into something new.
Ice melting, sugar dissolving, and metal rusting — which of these are chemical changes?
Only metal rusting — it forms a new substance (iron oxide).
What is plasma and where is it commonly found?
A high-energy state of matter with charged particles; found in the Sun, lightning, and stars.
What happens to the temperature during a phase change?
The temperature stays the same while the substance changes state.