physical vs. chemical
A change that results in the formation of a new substance.
a chemical change
A 2.75 kg sample of a substance occupies a volume of 250.0 cm3 . Find its density in g/cm3 .
11 g/cm3
C2H5O
How many atoms of oxygen?
1
Sodium chloride (NaCl) is an example of an atom.
false - it is a compound
The amount of mass per unit volume, or amount of something in a specific space
density
This a change that can be observed or measured without changing the composition of the substance.
What is physical change?
A solid object listed below has a volume of 10.0 cm3 . It has a mass of 86 g. What is its density?
8.6 g/cm3
Ca(OH)2
How many atoms of hydrogen (H)?
2
flammability is a physical property
false - chemical
Only one type of molecule or element grouped together
pure substance
Rusting, tarnishing, reacting with, cooking, decomposing, burning, etc are examples of what type of change?
chemical change
The density of silver (Ag) is 10.5 g/cm3 . Find the mass of Ag that occupies 965 cm3 of space.
1.01 x 104 g Ag (10100 g Ag)
Cu2Cr2O77
How many atoms in total in the compound?
11 atoms
To calculate density, you must divide the mass by the volume of an object.
True
A group of chemically bonded atoms that must have more than one type of element
compound
Salt dissolving into water is an example of what type of change?
physical change
Find the volume that 35.2 g of carbon tetrachloride (CCl4) will occupy if it has a density of 1.60 g/mL.
22.0 mL
Cr3(PO4)2
How many atoms in total for the compound?
13 atoms
A banana rotting over a period of time is an example of a physical change.
false - It is chemical.
A mixture which can easily be separated, such as a salad
heterogeneous mixture
Carbon dioxide and water reacting together to form glucose and oxygen is the reaction for photosynthesis. What is this type of change?
chemical change
Under certain conditions, oxygen gas (O2) has a density of 0.00134 g/mL. Find the volume occupied by 250.0 g of O2 under the same conditions.
1.87 x 105 mL (187000 mL)
Fe(H2PO4)3
How many atoms are within the parentheses?
21 atoms
A compound is an example of a pure substance.
true
A mixture where you cannot easily see the two separate components
homogeneous mixture