Physical and Chemical Properties
What are the states of matter?
Solid, liquid, gas, plasma
Define a physical change.
The form or appearance of matter changes, but not its composition
What is known as the universal solvent?
water
True or false: All matter is constantly in motion?
True, matter is composed of tiny particles that are in constant motion.
What type of property can be observed without altering the composition of the sample?
physical property
Is dissolving lemonade mix in water a physical or chemical change?
physical change
Give an example of a pure compound.
elements or compounds
What is the difference between the volume of a liquid and a gas?
Volume of a liquid is defined
Volume of a gas is not defined
Name five of the ten physical properties commonly used to identify substances.
(Any of the following) Color, shape, smell, taste, texture, mass, volume, density, melting point, boiling point
After leaving your bicycle in the rain, you notice a small chip in the paint leads to an area of reddish, powdery substance. What type of change has occurred here and what is the new substance called?
Chemical change
rust
What is the difference between heterogenous and homogenous mixtures?
Heterogenous mixture are not mixed evenly and homogenous mixtures are mixed evenly on a molecular level (aka solutions)
An object (gains/loses) thermal energy when changing from a solid to a liquid. An object (gains/loses) thermal energy when changing from a liquid to a gas.
Gains
Gains
(think the particles are moving faster due to increased energy absorbed)
Give an example of a size-dependent and size-independent property.
Size-dependent: Mass, weight, volume
Size-independent: density, melting/boiling point, solubility, ability to attract a magnet, state of matter, color
Define the law of conservation of mass
Mass cannot be created or destroyed
What is the rule for dissolving solutes in solvents?
"Like dissolves like"
"Polar dissolves polar"
"non polar dissolves non polar"
An object will float under what conditions of density?
When the object is less dense than the fruit it is in, it will float. If the object is more dense than the liquid it occupies, it will sink.
ex. acidity, flammability, reactivity, heat of combustion
What are the four signs of a chemical change?
Changes in energy, color, odor, the production of gases/solids
Acids release H+ ions and produce ___________ ions when dissolved in water. Bases accept H+ ions and produce _________ ions when dissolved in water.
Acids- Hydronium ions
Bases- Hydroxide ions
When you breathe in, your diaphragm contracts and expands the volume of your lungs to allow more air in. When you diaphragm relaxes, it presses on your lungs, decreasing the volume of your lungs, pushing out the air. At what point is the pressure in your lungs the highest?
When your lungs are contracting due to your diaphragm relaxing. The amount of air has not changed, but the size of the area it is occupying has gotten smaller. (Pressure= force/area)