Intro to matter
what is matter?
anything that has mass and takes up space
What is an example of a chemical property
flammability
What is an example of a physical change
hair cut, dissolving sugar in water,....
What is the difference between an element and a compound
element is 1 type of atom and a compound is multiple types of compounds
What is a mixture?
a variety of elements and compounds that are not chemically combined with each other
Which of these is denser a golf ball or a table tennis ball.
golf ball
What are 3 examples of a physical property
density, solubility, melting point
What is an example of a chemical change
burning a candle, rust on a car....
What is a pure substance
A substance with a definite chemical and physical properties.
what types of properties can separate a mixture
what is the difference between weight and mass
What is a good property to use to identify gold vs. iron pyrite
density
What is the law of conservation of mass
Mass can not be created or destroyed only transformed
How can elements be classified
metals, nonmetals, metalloids
How can you classify a mixture
Suspensions, solutions, colloids
What is the volume of a substance that displaces water from 20 mL to 32.43 mL
12.43 mL
What is a property of aluminum foil
silver, malleable, ....
What are 3 signs of a chemical change
production of gas, production of odor, change in color, change in energy, formation of a precipitate
how can compounds be classified
by their pH, organic or inorganic, role in the body
What is an example of each type of mixture
suspension: snow globe
Solution: tea
Colloid: gelatin
What is the density of a substance with a mass of 55 grams and a volume of 6 cm^3
9.17 g/cm^3
What is the difference between chemical and physical properties
Chemical properties change the identity of the substance physical properties change the appearance.
A log ways 1 kg. After burning it the ash ways 0.5 kg. Where did the other 0.5 kg go.
It turned into smoke
How does the pH scale work
below 7=acid
7=neutral
above 7= basic
What is the difference between homogeneous and heterogeneous mixtures
homogeneous: substances in a mixture are evenly spread throughout
heterogeneous: a mixture that does not have a uniform composition.