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GCSE Chemistry C4 (OCR)

Usman Rauf Chemistry GCSE English 4.4Average rating 4.4 out of 5 (7 ratings) 47 cards

Cards in this deck (47)

  1. 1Atoms of each element have different ______ numbers.Proton.
  2. 2Why is arranging elements based on their proton number beneficial?...because it gives repeating patterns in the properties of elements.
  3. 3What were the significant stages in the history of the development of the periodic table?- Chemists compared the masses of atoms with the mass of the lightest, hydrogen. This is called the relative formula mass.
    -Dobereiner: Groups of 3 had similar properties. RAM of element 2 = Mean of RAM of 1 + 3.
    Newlands: In order of RAM, every 8th element had similarities. Only worked for 1-16.
    Mendeleev: RAM, leaving gaps for undiscovered elements.
  4. 4How did Mendeleev use his Periodic Table to predict the existence of unknown elements?He looked for gaps within the expected similarities.
  5. 5How can you use the Periodic Table to identify the names, symbols, relative atomic masses and proton numbers of elements?Top No. = Relative Atomic Mass
    Letter = Symbol
    Word = Name
    Bottom No. = Proton Number
  6. 6What is each vertical column of the Periodic Table?A group.
  7. 7What are the chemical symbols for Lithium, Sodium, and Potassium? What are these known as?Lithium = Li
    Sodium = Na
    Potassium = K
    These are the Alkali Metals. They react with water to form alkaline compounds.
  8. 8What happens to a freshly cut alkali metal?They are shiny when freshly cut, but tarnish rapidly in most air due to a reaction with oxygen.
  9. 9How do Lithium, Sodium, and Potassium react with cold water?Lithium: Floats, fizzes gently, disappears.
    Sodium: Skids, fizzes, disappears.
    Potassium: Catches fire, moves quickly, disappears.
  10. 10When the alkali metals react with water, what do they form?They form their hydroxides (eg. Sodium hydroxide) and hydrogen.
    The formula is MOH
  11. 11When the alkali metals react with chlorine, what do they form?They form their chlorides (salts), (eg. Sodium chloride).
    The formula is MCl
  12. 12Do the alkali metals become more or less reactive as the group is descended? What is the evidence for this?More reactive.
    Melting points and boiling points decrease as the group is descended.
  13. 13What are the main hazard symbols?Explosive, harmful, toxic, corrosive, oxidising, highly flammable.
  14. 14What precautions should be taken when working with Group 1 metals and alkalis?Use forceps and wear goggles.
  15. 15What are the chemical symbols for the Group ___ elements chlorine, bromine, and iodine?7
    Chlorine = Cl2
    Bromine = Br2
    Iodine - I2
  16. 16What state are the Halogens in at room temperature and pressure?Chlorine: Gas
    Bromine: Liquid (+ Vapour)
    Iodine: Solid (+ Vapour)
  17. 17What colour are the Halogens at room temperature and pressure? And as gasses?Chlorine: Green, Green
    Bromine: Red, Red-Brown
    Iodine: Grey, Purple
  18. 18What do the Halogens consist of?Diatomic molecules, so the atoms are joined in pairs.
  19. 19Do the Halogens become more or less reactive as the group is descended? What is the evidence for this?Less reactive.
    The boiling and melting points increase as the group descends.
  20. 20How can a trend in reactivity be shown by the Halogens?Iodine solution can be used to treat infections, but chlorine solution is much too reactive to do this.
    Iron glows strongly in chlorine gas, but doesn't glow in iodine vapour.
    Displacement reaction shows that Chlorine solution will displace bromine from its solution, so bromine will form and the solution will turn red.
  21. 21What safety precautions need to be taken when working with Halogens?Wear eye protection, wear chemical resistant gloves, make the reactions in a fume cupboard.
  22. 22What are the formulae of hydrogen, water, and halogen molecules?Hydrogen = H2
    Water = H20
    Halogens = Cl2, Br2, I2
  23. 23What are the formulae of the chlorides, bromides, and iodides (halides) of Group 1 metals?Chlorides = LiCl, NaCl, KCl
    Bromides = LiBr, NaBr, KBr
    Iodides = LiI, NaI, KI
  24. 24How do you write word equations for reactions of alkali metals and halogens?Eg. Cl2 + Br ---> BrCl2
  25. 25What is the structure of an atom?The protons and neutrons are in the nucleus, with the electrons arranged in shells around the nucleus.
  26. 26What are the relative masses and charges of protons, neutrons, and electrons?Neutron = 1, 0
    Proton = 1, +1
    Electron = Negligible, -1
  27. 27In any atom, the number of _______ equals the number of ________.Electrons
    Protons
  28. 28How are the elements in the Periodic Table arrangedIn order of proton number.
  29. 29When heated, what do some elements emit? (Eg. Lithium, Sodium, Potassium).Distinctive flame colours.
  30. 30What does the light emitted from each element give?A characteristic line spectrum.
  31. 31What has the study of spectra helped chemists to do?Discover new elements.
  32. 32What did the discovery of some elements depend upon?The development of new practical techniques, such as spectroscopy.
  33. 33How can you use the Periodic Table to identify the number of protons, neutrons, and electrons in an atom?Proton No. = No. of protons
    Top No. = No. of electrons in each shell
    No. of protons = No. of neutrons
  34. 34How can you represent the arrangements of atoms?2.8.1
    2 full shells of electrons, 1 electron on the outer shell.
  35. 35What does each shell fill with?Electrons
  36. 36What do the outer shells of elements in the same group have in common?They have the same number of electrons.
  37. 37What are the chemical properties of an element determined by?The number of electrons in the outer shell.
    Eg. One or two = Metal.
    Two + = Non-Metal
  38. 38Molten compounds of metals with non-metals ______ _______. What is this evidence for?Conduct Electricity.
    They are made up of charged particles called ions. In a solid, the particles cannot move towards the electrode, so the compound cannot conduct electricity.
  39. 39What happens during electrolysis?The negative electrode attracts the positive ions. The positive electrode attracts the negative ions. The ions lose their charges and turn back into atoms.
  40. 40What is an ion?An atom that has gained or lost electrons, and so has an overall charge.
  41. 41How can you account for the charge on the ions of Group 1 and Group 7 elements?The ions of group 1 elements are positive, because they lose an electron.
    The ions of group 7 elements are negative, because they gain an electron.
  42. 42How can you work out the formulae of ionic compounds given the charges of the ions?The charges have to cancel each other out.
  43. 43How can you work out the charge on one ion given the formula of a salt and the charge on another ion?The charges have to cancel each other out.
  44. 44Compounds of Group 1 metals with Group 7 elements are _____.Ionic.
  45. 45What do solid ionic compounds form? Why?Crystals, because the ions are arranged in a regular lattice.
  46. 46What happens to the ions when an ionic crystal melts or dissolves in water?-
  47. 47When and why do ionic compounds conduct electricity?-

Information

Description
A selection of revision cards for GCSE Chemistry topic C4, on the OCR board. All question have been developed from the specification.
Created by
Usman Rauf
Views
459
History
  • Created by Josh Price · Apr 16, 2015
  • Copied by Usman Rauf · Apr 16, 2015
Rating
Average rating 4.4 out of 5 (7 ratings)

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