A 3.1 L sample of hydrogen <u>d. contains the same number of molecules</u>
as 3.1 L of carbon dioxide at the same temperature and pressure.
This is the fundamental principle of <em>Avogadro’s hypothesis</em>: equal volume of gases at the same temperature and pressure contain the same number of molecules.
The sample of carbon dioxide has a <em>greater mass</em>, a <em>greater number of atoms</em>, and a <em>greater density</em>, than the sample of hydrogen.
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).
