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90 Cards in this Set
- Front
- Back
What are ions? |
Electrically charged particles |
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How are ions formed? |
When atoms loose or gain electrons |
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The structure of ions are similar to what? |
Noble gases |
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What sort of ions do metals form? |
Positive (loss of electrons) |
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What holds ions together? |
The strong electrostatic forces of attraction between oppositely charged ions (ionic bond) |
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What type of metals are found in Group 1? |
Alkali metals |
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What are involved with an ionic bond? |
Metal and Non- Metal |
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What are involved in a covalent bond? |
Non-Metals |
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What do covalent bonds form? |
Molecules |
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What holds an ionic lattice together? |
Strong electrostatic forces of attraction between oppositely charged ions |
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When do ionic compounds conduct electricity? |
Molten or in a solution |
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What is a mixture? |
Two or more elements/compounds that aren't chemically bonded, properties remain unchanged |
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What is a compound? |
Two or more elements chemically bonded together, arrangement of outer shell changes |
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What are the properties of simple molecular compounds? |
Low melting and boiling points due to strong covalent bonds but weak intermolecular forces |
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What is the term for giant covalent structures? |
Macromolecules |
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Give 3 examples of giant covalent structures |
Diamond |
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What are the properties of a covalent bond? |
Low melting and boiling points due to the fact that they form molecules with strong covalent bonds but weak intermolecular forces of attraction |
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What are diamond and graphite examples of? |
Allotropes, in this case carbon |
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What are fullerenes? |
Hexagonal rings of carbon atoms |
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What is an example of a fullerene? |
Buckminsterfullerene |
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What are the properties of graphite? |
Soft and slippery due to the fact that graphite is arranged in layers |
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Why can metals conduct electricity? |
Electrons in outer shell become delocalised because the atoms are so tightly packed so the layers overlap |
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Why are alloys stronger than pure metals? |
Because the mixture of different shaped atoms disturbs the regular arrangement of layers meaning the layers can't slide |
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Name some uses of shape memory alloys |
Dental braces |
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Name an example of a shape memory alloy |
Nitinol |
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What varies the properties of polymers? |
What monomer was used to make the polymer |
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Why are LDPE and HDPE different? |
Different catalysts were used |
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What does a thermo-softening polymer consist of? |
Individual polymer chains that are tangled together |
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What are the properties of thermo-softening polymers? |
Can be softened and shaped when heated |
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What are isotopes? |
Elements that are the same but have a different number of neutrons |
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How small is a nanometre? |
1 billionth of a metre |
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What are diamond and graphite made from? |
Carbon atoms |
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How is diamond structured? |
In a giant covalent structure |
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How many bonds does 1 carbon atom form to other carbon atoms in diamond? |
4 |
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Why is diamond such a hard substance? |
Due to the large number of strong covalent bonds |
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How is graphite structured? |
In a giant covalent structure |
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How many bonds does 1 carbon form with other carbon atoms in graphite? |
3 |
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What properties does a layered structure create in graphite? |
The layers can slide over each other resulting in a soft and slippery substance that can be used as a lubricant |
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What are the layers held together by in graphite? |
Weak intermolecular forces of attraction |
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How are metals arranged? |
Layers, regular lattice of positive ions held together by strong electrostatic forces of attraction |
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What are shape memory alloys? |
They are alloys that respond to changes in the environment and remember their shape |
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What are the properties of thermo-setting plastics? |
Polymer chains joined by cross links |
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What is created when nanoparticles combine? |
Nanostructures |
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What is nanoscience? |
The study of very small structures |
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Why are the properties of nanoparticles different to the same material in bulk? |
Nanoparticles are more sensitive to light, heat and magnetism |
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The research of nanoparticles may lead to what? |
New catalysts |
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What are fullerenes used for? |
Deliver drugs in the body |
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What is the relative formula mass? |
Total mass of a compound |
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How do you calculate the percentage mass? |
Relative mass of element in compound |
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What is the empirical formula? |
Simplest whole number ratio of each kind of atom |
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What is a mole? |
Number of particles (atoms or molecules) in a substance |
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What is 1 mole equal to? |
The relative formula mass |
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How big is a mole? |
6x10^23 |
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How do you calculate the number of moles in a substance? |
Mass of substance |
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What is chromatography used for? |
Identify substances within an unknown substance |
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What are the steps of chromatography? |
1. Sample of unknown substance is placed on the start line of a piece of paper |
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What is the yield? |
Amount of product obtained |
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Why is it not possible to obtain the maximum amount of product? |
If reaction is reversible it might go to completion |
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How do you calculate the percentage yield? |
Yield from Reaction |
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What factors affect the rate of reaction? |
Use of catalyst |
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How do you calculate the rate of reaction? |
Amount of reactants used/product formed |
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What is an exothermic reaction? |
Temperature rise |
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Give some examples of an exothermic reaction |
Neutralising alkalis with acids |
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What products use exothermic reactions? |
Hand warmers |
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What is an endothermic reaction? |
Fall in temperature |
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Give examples of an endothermic reaction |
Thermal decompostition |
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What products use endothermic reactions? |
Instant sports injury ice packs |
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What does a mass spectrometer measure? |
Relative molecular mass |
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What does a catalyst do? |
Reduces amount of energy needed for successful collision (activation energy) |
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Why is surface area important in terms of the rate of reaction? |
Smaller pieces have a larger surface area in comparison to their volume |
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What is an alkali? |
Bases dissolved in water |
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What colour do alkalis turn red litmus paper? |
Blue |
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What colour do acids turn blue litmus paper? |
Red |
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When an acid is dissolved in water, what's produced? |
Hydrogen ions (H+) |
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When an alkali is dissolved in water, what's produced? |
Hydroxide ions (OH-) |
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What is produced when hydrogen and hydroxide ions react? |
Water |
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Acid + Metal Oxide=? |
Salt + Water |
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Acid + Metal Hydroxide=? |
Salt + Water |
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Acid + Metal=? |
Salt + Hydrogen |
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How can you predict the name of the salt produced in a neutralisation reaction? |
The first part of the name is always the first part of the base |
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What is ammonia? |
An alkaline gas |
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What industry is it used in? |
Production of fertilisers |
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Ammonia neutralises nitric acid to produce what? |
Ammonium nitrate- This is used in fertilisers |
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Why are nitrogen based fertilisers so important? |
Increases the yield of crops |
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What problems can nitrates cause? |
Upset the natural balance of water |
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What is electrolysis? |
Breaking down of a compound containing ions into its elements using an electrical current |
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What is the substance called which is broken down in electrolysis? |
Electrolyte |
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What is a redox reaction? |
Where both reduction and oxidation reactions occur |
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What is a reduction reaction? |
When positively charged ions gain electrons at the negative electrode |
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What is an oxidation reaction? |
When negatively charged ions lose electrons at the positive electrode |