Flashcards in Atomic structure, analysis and quantitive chemistry Deck (9)
Explain why the mass number of oxygen is 16.
You should refer to the numbers of sub-atomic particles in the nucleus of the atom. 
there are 8 protons and 8 neutrons (in the nucleus)
Explain why carbon-12 and carbon-14 are isotopes of carbon.
You should refer to the numbers of sub-atomic particles in the nucleus of each isotope. 
- both atoms have the same number of protons
- carbon-12 has 6 neutrons
- carbon-14 has 8 neutrons
One mole of a substance is the relative formula mass in ______.
The relative atomic mass of an element compares the mass of an atom of an element with the mass of an atom ______. 
Metal oxides react with acids to make salts.
What type of compound is a metal oxide? 
State how solid lead nitrate can be obtained from lead nitrate solution. 
by evaporation / crystallisation
Why do different compounds separate in a gas chromatography column? 
different substances travel at different speeds
Give one reason why the calculated yield of magnesium might not be obtained. 
- the reaction is reversible
- some get lost / released
- some of the reactant may react in different ways
What is the purpose of gas chromatography?