TOPIC 1 - Atomic Structure and the Periodic Table✅ Flashcards
What is the radius of Atoms?
0.1 Nanometers.
Where is the Nucleus in an Atom?
In the middle.
What does the Nucleus contain?
Protons and Neutrons.
What is the radius of the Nucleus?
1 x 10 to the power -14 m.
What charge does the Nucleus have?
Positive charge.
Almost the whole mass of the atom is….
The nucleus.
Give 3 facts about Electrons:
- They move around the nucleus in electron shells.- Negatively charged.- Have almost no mass.
Give the RELATIVE MASS and RELATIVE CHARGE of Proton:
1+1 (positive)
Give the RELATIVE MASS and RELATIVE CHARGE of Neutron:
1 0 (neutral)
Give the RELATIVE MASS and RELATIVE CHARGE of Electron:
Very small-1 (negatively charged)
What does the atomic number tell you?
The number of protons and electrons.
What does the mass number tell you?
The number of protons and the number of neutrons.
How to find the number of neutrons:
MASS NUMBER - ATOMIC NUMBER.
Where is the atomic number?
At the bottom.
Where is the mass number?
At the top.
What is the charge in an atom?
NEUTRAL. NO CHARGE OVERALL.
Why are atoms neutral?
Because they have the same number of protons as electrons.
What is an ION?
An atom or group of atoms that have lost or gained electrons.
IN A POSITIVE ION. How do you find the number of electrons?
ATOMIC NUMBER - CHARGE.
IN A NEGATIVE ION. How do you find the number of electrons?
ATOMIC NUMBER + CHARGE.
In an ion, the number of protons doesn’t equal the number of electrons. What does this mean?
It has an overall charge.
What does it mean if an ION has a 2- charge?
It has 2 more electrons than protons.
What is an element?
A substance made up of atoms that all have the same number of protons in their nucleus.
Elements are made up of….
Atoms with the same Atomic Number.
The smallest part of an element that you can have is….
A single atom of that element.
The number of protons in the nucleus decides…
What type of atom it is.
An atom with one proton is…
Hygrogen.
If a substance only contains atoms with the same number of protons it’s called….
An element.
Atoms can be represented by Symbols. Give the symbol for Magnesium.
MG.
What are Isotopes?
Atoms with the same number of protons but a different number of neutrons.
Isotopes have the same atomic number but….
different mass numbers.
If an element has a different number of isotopes, how can you describe it?
Using relative atomic mass ( A r) instead of mass number - this is an avergae mass.
FORMULAE TO WORK OUT RELATIVE ATOMIC MASS:
SUM OF (Isotope abundance (amount) x Isotope mass number) DIVIDED BY sum of abundances of all the isotopes.
When two or more elements react, what do they form?
Compounds.
What are compounds?
Substances that contain atoms of different elements.
What are atoms held together by in a compound?
Chemical bonds.
What is the only way to seperate elements in a compound?
By using a chemical reaction.
What does a formula show?
What atoms are in a compound.
What do word equations show?
The names of the chemicals that are reacting and being produced.
Give 2 points about MIXTURES:
- Mixtures contain at least two different elements or compounds.- There aren’t any chemical bonds between the different parts of the mixture.
Air is a mixture of gases, mainly….
nitrogen, oxygen, carbdon dioxide and argon.
Give the 5 physical methods that can seperate different parts of a mixture:
- Filtration.- Crystalisation.- Simple Distillation.- Fractional Distillation.- Chromatography.
What can Chromatography be used for?
It can be used to separate different dyes in an ink.
List the 8 steps to CHROMATOGRAPHY:
1) Draw a line near the bottom of a sheet of filter paper in pencil so it won’t dissolve.2) Add a spot of ink to the line.3) Add a small amount of solvent into the beaker so it forms a shallow layer.4) Place the sheet in the beaker and make sure the ink isn’t touching it so it won’t dissolve.5) Place a kid on top of the container to stop the solvent from evaporating.6) When the solvent has nearly reached the top of the paper, take the paper out of the beaker to dry.7) Each ink moves up the paper at different speeds which separates it. There should be one spot for each dye in the ink.
What is the pattern of spots that happens as a result of Chromatography called?
Chromatogram.
What does FILTRATION separate?
Insoluble solids from liquids.