C1 Atoms Bonding and Moles Flashcards
What is the charge, relative mass, and location of a proton
Charge +1
Relative mass 1
Location nucleus
What is the charge, relative mass, and location of a neutron
Charge 0
Relative mass 0
Location nucleus
What is the charge, relative mass, and location of an electron
Charge -1
Relative mass 1/1836 (18x2=36)
Location energy shells
What is the mass number of the element
The number of protons and neutrons
What is the atomic number
The number of protons ( and electrons but don’t say in exam 🚬🚬🚬)
How do you work out the number of neutrons
Mass no - atomic no
When was John Dalton around and what was his theory on atoms?
Start of 19th century ( 1800s )
Atoms were first described as solid spheres
Each chemical element had its own atoms that differed from others in their mass
Believed that atoms could not be divided or split
When did Thompson make his theory and what was it?
He was in 1897
He found that atoms were attracted to positive charge so they must be negatively charged themselves
Called them electrons
Suggest plum pudding model: sphere of positive charge, electrons embedded in it ( like bits of plum in plum pudding )
When was Ernest Rutherford and what did he discover
1909
Discovered the nucleus by Alpha scattering experiment: shooting a beam of alpha particles ( positive ions ) at thin gold foil ( a couple atoms thick ) and some atoms passed through, some bounced off in all directions ( going through empty space or hitting nucleus and repelling because of both positive charge ). Suggesting a tiny ball of positive charge in middle of the atom with electrons orbiting it and most of the atom is empty space.
When was Neils Bohr and what did he discover
1914
Electrons are in fixed shells orbiting the nucleus
- realised this when electrons where heated the light produced only had a specific amount of energy so the energy must be given when and excited electron goes from a high energy level to a low one
When was James chadwick and what did he discover
Around 1940
Discovered that there are neutrons in the nucleus because there needed to be more sub atomic particles to fill out the atomic number
Describe the evolution of the atomic model, give dates
400BC: basic shapes and concept of building blocks
1800: balls that make up everyday object
1897: plum pudding, ball of positive charge with electron in it
1909: ball with nucleus in it with positive charge and electron orbiting it
1911: nucleus with fixed energy shells of electrons orbiting
1932: nucleus with neutrons and protons with fixed energy shells of electrons
Give two elements that Dalton created which are not in the modern day periodic table
Soda
Lime
How many electrons can each of the energy shells contain
1st: 2 electrons
2nd: 8
3rd: 8 in GCSE
Remaining go into 4th shell ⛏
What does the reactivity of the element depend on and why
It depends on the stability of the electronic structure( how many electron in the outershell ). Because if they have only electron to complete or to get whole shell then they will react more vigorously to get rid of it
