Atoms and compounds. Flashcards
Which number is the mass number?
The one on the top
What is the mass number?
The number of Protons added to the amount of neutrons
What is the number on the bottom?
Atomic number
What is the atomic number?
The number of protons in the nucleus (also the number of electrons)
What are Isotopes?
Isotopes are atoms with the same amount of protons but a different amount of neutrons
How is a molecule formed?
When two or more atoms bond together
How do you calculate the molecular mass?
Add up the atomic masses of the elements within in the molecule
How do you calculate the % composition?
% X= (mass of X in compound / molecular mass)*100
What do electrons do?
Orbit the nucleus in the energy shells
Where are protons found, what is their mass and what is their charge?
They are found in the nucleus, they have a mass of 1 and a charge of +1
Where are neutrons found, what is their mass and what is their charge?
They are found in the nucleus, their mass is 1 and they have a charge 0
Where are electrons found, what is their mass and what is their charge?
They are found in the energy shells, their mass is 0 and they have a charge of -1
Why are all atoms neutral?
Because they all have the same amount of protons and electrons.
How are ions formed?
If the atom gains or loses electrons then their charge changes.
Why do atoms gain or lose electrons?
To obtain a full outer shell
