C4 - The Periodic Table Flashcards
C4 - The Periodic Table
What is a neutron?
Has 0 charge and a relative atomic mass of 1
C4 - The Periodic Table
What is an electron?
Has a charge of -1 and a relative atomic mass of 0.0005
C4 - The Periodic Table
What is a proton?
Has a charge of +1 and a relative atomic mass of 1
C4 - The Periodic Table
What is the atomic number?
(BOTTOM NUMBER) The number of protons (or number of electrons)
C4 - The Periodic Table
What is the mass number?
(TOP NUMBER) Number of neutrons plus number of protons
C4 - The Periodic Table
What is the order of reactivity for Group 1?
As they go down the group, the reactivity increases (get more reactive)
C4 - The Periodic Table
What is the order of reactivity for Group 7?
As they go down the group, the halogens become less reactive
C4 - The Periodic Table
What produces a white precipitate?
Chloride ions
C4 - The Periodic Table
What produces a cream precipitate?
Bromide ions
C4 - The Periodic Table
What produces a pale yellow precipitate?
Iodide ions
C4 - The Periodic Table
What are the processes in water purification?
Filtration, Sedimentation, Chlorination
C4 - The Periodic Table
What is filtration?
A layer of sand or gravel filters remaining small particles and sometimes removes microbes
C4 - The Periodic Table
What is sedimentation?
Chemicals are added to make solid particles and bacteria settle
C4 - The Periodic Table
What is chlorination?
Chlorine is added to kill remaining microbes
C4 - The Periodic Table
What pollutants are found in water?
Nitrates - from fertilisers via eutrophication Lead compounds - from water pipes to houses Pesticides - from spraying crops
C4 - The Periodic Table
What is a superconductor?
Materials which can conduct electricity with little or no resistance
C4 - The Periodic Table
What are the two types of superconductor?
Type I - metals Type 2 - alloys
C4 - The Periodic Table
What are the benefits of superconductors?
Loss free power transmission, superfast electronic circuits and powerful electromagnets
C4 - The Periodic Table
What are the difficulties with superconductors?
They only work at very low temperatures, limiting their use and superconductors that work at room temperature need to be developed.
C4 - The Periodic Table
What is the Period number?
(ROWS - ACROSS) Number of electron shells
C4 - The Periodic Table
What is the Group number?
(COLUMN - DOWN) Number of electrons in outer shell
C4 - The Periodic Table
What is an isotope?
An atom of the same element but with different mass numbers (different number of neutrons)
C4 - The Periodic Table
Give one example of an isotope…
Carbon-12 and Carbon-14
C4 - The Periodic Table
What did John Dalton do?
(1803) Said atoms where solid spheres and there was a different sphere for each element
C4 - The Periodic Table
What did J.J Thomson discover?
(1897) That atoms weren’t solid spheres and there were negatively charged particles - electrons. Theory was called the “Plum Pudding Model”.
C4 - The Periodic Table
How did Rutherford describe the atom?
(1911) Theory of the Nuclear Atom - Gold Foil experiment found that the positive nucleus was surrounded by negative electrons after positive particles passed through the gold, rather than be deflected.
C4 - The Periodic Table
What did Niels Bohr describe?
(1913) Electrons had fixed orbits and fixed energy which prevented the electrons being attracted to the positive nucleus. They orbited in shells.
C4 - The Periodic Table
What are the properties of ionic compounds?
Typically dissolve in water, conduct electricity when in a solution/molten, have very high melting points and their structures are described as giant ionic lattices.
C4 - The Periodic Table
What is a covalent bond?
A shared pair of electrons
C4 - The Periodic Table
lithium + water
lithium hydroxide + hydrogen (2Li + 2H₂O → 2LiOH + H₂)
C4 - The Periodic Table
sodium + water
sodium hydroxide + hydrogen (2Na + 2H₂O → 2NaOH + H₂)
C4 - The Periodic Table
potassium + water
potassium hydroxide + hydrogen (2K + 2H₂O → 2KOH + H₂)
C4 - The Periodic Table
Why is potassium more reactive than lithium?
Because potassium is able to lose its outer electron easier than lithium because the larger radius means that the force of attraction from the nucleus is weaker.
C4 - The Periodic Table
What colour flame does lithium produce?
Red or crimson
C4 - The Periodic Table
What colour flame does sodium produce?
Orange
C4 - The Periodic Table
What colour flame does potassium produce?
Purple or lilac
C4 - The Periodic Table
What is the method for the flame test?
Wash the nichrome wire to clean and make compound stick. Dip into metal compound and hold in Bunsen Burner to produce coloured flame. Repeat with different metal compound.
C4 - The Periodic Table
What are halogens?
Salt formers’ - they (Group 7s) react with Group 1 to make salts
C4 - The Periodic Table
Potassium + chlorine
potassium chloride (2K + Cl₂ → 2KCl)
C4 - The Periodic Table
Sodium + chlorine
sodium chloride (2Na + Cl₂ → 2NaCl)
C4 - The Periodic Table
Potassium + bromine
potassium bromide (2K + Br₂ → 2KBr )
C4 - The Periodic Table
Complete and what is this an example of: Cl₂ + 2NaBr
2NaCl + Br₂ an example of a displacement reaction
C4 - The Periodic Table
What elements are bonded by covalent bonds?
Non metals. E.g. Hydrogen (H₂) or Carbon Dioxide (CO₂)
C4 - The Periodic Table
Which elements are bonded ionically?
A metal and a non metal. E.g. Magnesium and oxygen forms magnesium oxide.