Answer:
I pretty sure it's the pH level 7
The mass per volume of a substance is called its density.
Answer:Boiling water is a physical change, as it rearranges molecules but does not affect the internal structures. Boiling water forces the water molecules away from each other as the liquid changes to vapor. In a chemical change, new chemical substances are created or formed. Advertisement. Physical changes affect the state of an item, and a chemical change happens at a molecular level.
Explanation:
hope it helps:))
Answer:
b) Silicon and oxygen
Explanation:
A compound is a pure substance that contains two or more atoms chemically joined together. Sand is regarded as a 'compound' because it is made up of two or more atoms that are chemically bonded to one another.
Sand is said to predominantly contain silica, which has a chemical formula of SiO2. Hence, sand can be said to be a compound containing one atom of silicon (Si) and two atoms of oxygen (O2).
