Topic 1 - INSIDE THE ATOM Flashcards
what is the radius of the nucleus
around 1 x 10^-14 m
where is most of the mass of an atom concentrated
in the nucleus
what is the radius of an atom
around 1 x 10^-10 m
0.1 nanometres
what is a mass number
sum of protons and neutrons in an atom
what is an atomic number
number of protons
or electrons
how do you find the number of neutrons in an atom?
Mass number- atomic number
what is an isotope
different forms of the same element with the same number of protons but different number of neuutrons
what is a covalent bond?
A bond formed when two atoms share a pair of electrons
what is a molecule
a particle made up of at least two atoms held together by covalent bonds
Halogens
Non-metals with coloured vapours
As you go down group 7:
- become more reactive- distance between nucleus and shells is greater the force of attraction between electrons is weaker - intermolecular force between electrons and nucleus is weaker making it harder for electrons to be gained
-Melting and boiling point increases:
•the molecules become larger
•the intermolecular forces become stronger
•more energy is needed to overcome these forces
- higher relative atomic mass
Form ionic bonds with metals
Can form molecular compounds
what is relative atomic mass ?
● Relative atomic mass: an average
value that takes account of the abundance of
the isotopes of the element
consequences of climate change
•icecaps melting- sea levels rising-flooding- some species less successful hunters e.g. polar bears
•Meteorological events-Extreme meteorological events, such as storms, heatwaves and droughts, could increase in frequency and intensity
•Changes in water availability could affect how species are distributed.
•The quantity, timing and distribution of precipitation could change. This would result in some regions receiving much less or much more rainfall than they previously did.
•Food shortages-A combination of some or all of these factors could hinder a region’s ability to produce food. This could lead to potential famines.
Changing weather patterns
how to reduce carbon footprint
You can reduce your carbon footprint by:
Maximise the efficiency of your energy use.
Minimise your waste.
Using renewable energy sources as an alternative to burning fossil fuels.
Carbon capture and storage
Carbon capture and storage refers to the capture of carbon dioxide produced by burning fossil fuels before it passes into the atmosphere.
Stores of this captured carbon are then kept deep underground.
Carbon off-setting
We can counteract emissions by planting trees, which will remove carbon dioxide from the atmosphere through the process of photosynthesis.
Carbon-neutral products
Carbon-neutral products don’t change the atmospheric carbon dioxide concentration.
what is a carbon footprint?
A carbon footprint is a measure of the total amount of greenhouse gases emitted as a result of a particular service, event or product.
how did john dalton arrange his periodic table
order of relative atomic mass
how did medeleev organise the periodic table
order of atomic weight- however did switch a few around as their properties fitted better in another area(group)
he left gaps for undiscovered elements with similar properties
How did john newlands organise his periodic table
Ordered his table in order of atomic
mass
● Realised similar properties occurred
every eighth element – ‘law of
octaves’ but broke down after
calcium.
Ar equation including abundance isotopes and ar)
Ar = (sum of isotope abundance x isotope mass number)/ sum of abundances of all the isotopes
E.g Cu-63 has an abundance of 69.2% and Cu-65 has an abundance of 30.8% calculate the relative atomic mass of copper
(69.2 x 63)+ (30.8 x 65)/ (69.2+30.8) =. 6361.6/100= 63.616
Briefly explain the process of fractional distillation to separate a mixture of the liquids methanol, ethanol and propanol.
Heat is applied and the liquid with the lowest boiling point evaporates and condenses into a beaker.
If other liquids evaporate by chance, they condense in the fractionating column back into the flask.
The temperature is altered to repeat the process for the second liquid.
The three liquids are separated based on differing boiling points with the third remaining in the flask.
What is an ion?
It is a charged particle when an atom loses or gains electrons
What is larger number on periodic table?
Atomic symbol
Or relative atomic mass
What is the modern name for atomic weight?
Relative atomic mass
Which sub atomic particle is relative mmass compared to ?
Proton
(it is 1)
How much smaller is the nucleus than the width from the nucleus to electron ?
X10000
