Calcium (Ca) and diatomic oxygen (O2) combine to form calcium oxide (CaO). The data table below compares the properties of these substances. Calcium (Ca) Oxygen (O2) Calcium Oxide (CaO)
Melting Point (°C) 842 −218.4 2613
Density (g/cm3) 1.54 0.00143 3.34
Appearance silvery-white
metal colorless,
odorless gas white, odorless
powder

What can be concluded from this data?
A.
A chemical reaction occurred because calcium oxide has different properties than calcium and diatomic oxygen.
B.
A chemical reaction did not occur because solid calcium cannot chemically react with diatomic oxygen gas.
C.
A chemical reaction did occur because calcium oxide has similar properties to calcium and diatomic oxygen.
D.
A chemical reaction did not occur because calcium oxide is not a new substance.