Atomic theory Flashcards
What is an element made up of?
Very tiny particles called atoms
How do atoms form compounds?
Atoms from one element join with atoms from other elements
What are atoms made up of?
Protons, neutrons and electrons
What are electrons?
Negatively charged particles
They spin around the positive nucleus of the atom in circles
What are protons?
Positively charged particles
What are electrons mass,charge and location?
Mass=0
Charge= -1
Energy level / around the nucleus
What are protons mass,charge and location?
Mass=1
Charge=1
in the Nucleus
What are neutrons mass,charge and location?
Mass=1
Charge=no charge
in the Nucleus
Why does the nucleus have an overall positive charge?
Because it contains only protons(positive) and neutrons(neutral)
Why does an atom have no overall charge?
Because they contain equal numbers of positive charges (protons) and negative (electrons)
These opposite charges cancel each other
Why does the atomic number do?
Tells you how many protons there are in an atom
What is the mass number?
It’s the number of protons + neutrons
What does a nucleitide looks like?
Mass number (top left) Atomic Number (bottom left)
And symbols of the elements.
What are isotopes?
They are atoms with the same atomic number but different mass numbers
What is RAM?
Is the average mass of all isotopes of a single element
What is an ion?
They are charged particles and they are formed when atoms lose or gain electrons
What happens when metal atoms lose electrons?
They form positive ions
What happens when non metal atoms gain electrons?
They form negative ions
What can be described about the noble gases?
They are stable as the have 8 on their outer energy level . This is why they are so unreactive
What does the number of protons equal to in an atom?
The number of electrons
what does a negative electron + positive metal ion make?
a strong electrostatic attraction - ionic compound
In an electrolysis, which electrodes will get the negative ions?
At the positive electrode
In an electrolysis, which electrodes will get the positive ions?
At the negative electrode
what are the names of
Group 1
Group 7
Group 8
Group 1: alkalis
Group 7: halogens
Group 8: Noble gases
What is the charge of the atom overall
Neutral, same amount of plus and negative
How to work out the RAM
% x mass no + %+ mass no
100
What is the RAM
Is the average mass of all isotopes within a single element
When is an ion formed?
Imbalance of electrons and protons
