Key Terms
Two or more substances that are physically blended together (no chemical bonding)
Mixture
What are the two types of mixtures?
Homogeneous
Heterogeneous
What is the formula for density?
Density = mass/volume
D=m/v
Which type of change can be easily undone?
Physical changes
Is hardness an intrinsic or extrinsic property?
Intrinsic (does not change with size)
How much matter is within an object is its __________.
Density
What are the two types of pure substances?
Elements
Compounds
An object with a density lower than water (1g/mL) will ___________.
Float
Burning a piece of wood, is an example of this type of change.
Chemical
Which type of substance is made up of only one type of atom?
Elements
This word means that the property does NOT change as the size of the sample changes.
Intrinsic
Give an example of a compound
Carbon dioxide CO2
Water H2O
Salt NaCl
Solve for density: an object has a mass of 150g and a volume of 10mL.
D= 150g/10mL
D= 15g/mL
Chemical changes change the ________________ of the substance.
Properties
Granite rocks with distinct layers are _____________
Heterogeneous Mixtures
What is the smallest building block of all matter?
An atom
Trail mix would be an example of what classification of matter?
A heterogeneous mixture
What are the two ways volume can be measured?
Water displacement
LxWxH
Give an example of a physical change you could do to a glass of water.
Freeze it, boil it, spill it out, add more water to it, etc.
Calculate the volume of a textbook that measures 12cm tall, 9 cm wide, and 4cm thick.
V = LxWxH
V = 12x9x4
V = 432cm3
Define matter
Anything that takes up space and has mass.
Classify Nitrogen gas (N2) as either a pure substance or mixture. Then specify further as heterogeneous, homogeneous, element, or compound.
Pure substance
Element
An object with a mass of 33g is dropped into a graduated cylinder and the water rises from 10mL to 43mL. What is the density of the object?
V = 43mL -10mL = 33mL
D= 33g/33mL
D= 1g/mL
Name one of the five key signs that a chemical change has occured?
New smell/odor
Fizzes/Bubbles
Precipitate forms in liquids
Unexpected color change
Temperature change
What holds compounds together?
Chemical bonds