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- @What is the best way to separate iodine from other impurities?
- Sublimation
- Dissolving and filtering
- Fractional distillation
-
- @The relative molecular mass of ammonium chloride NHÝCl?
- 53.5
- 50.5
- 60.0
-
- @An acid will always:
- React with an alkali to form a salt and water
- React with any metal to produce hydrogen
- Fume in moist air
-
- @A Hoffmann voltameter is connected as shown. The name of the negative (-) electrode is:
- #hoff
- The cathode
- The anode
- An ion
-
- @To break chemical bonds you:
- Give heat energy
- Remove heat energy
- Do not add or remove heat energy
-
- @Which one of the following is the most likely melting point of an ionic solid?
- 950Ì
- 0Ì
- -57Ì
-
- @Air, water, hydrogen, brass, silver nitrate & tin. From the list below, how many substances are elements?
- Two
- One
- Four
-
- @In a solid, if you supply more energy then:
- the more the particles vibrate
- the particles melt
- the bonds between the particles break straight away
-
- @Which of the following is incorrect for neutrons?
- They are similar in mass to electrons
- They carry no charge
- They do not orbit the nucleus
-
- @What is the name of the reducing agent used to obtain iron from its ore in a blast furnace?
- Carbon monoxide
- Calcium carbonate
- Hydrogen
-
- @Why are metals good conductors of electricity?
- They have many free moving electrons
- They have high melting points
- They are made of electrons only
-
- @What two substances are necessary for rusting to occur?
- Air and water
- Water and an oxide
- Oxygen and nitrogen
-
- @Which one of the following is NOT a property of diamond?
- Low melting point
- Transparent
- Does not conduct electricity
-
- @Which of the following is a chemical symbol for a halogen?
- I
- He
- Na
-
- @Hydrogen gas enters at the left, and is buring on the right. What can be seen on the cold surface?
- #burn
- Water droplets
- Soot
- Yellowish deposit
-
- @When hydrogen chloride gas mixes with ammonia gas:
- White fumes are formed
- There is an explosive reaction
- A dense black vapour is formed
-
- @Air is passed through sodium hydroxide solution, and then over heated copper. The gases removed during this process are:
- Carbon dioxide and oxygen
- Oxygen and water vapour
- Nitrogen and carbon dioxide
-
- @Sulphuric acid is made by the:
- Contact process
- Frasch process
- Electrolysis
-
- @What is the name of this substance?
- #eth
- Ethane
- Methanol
- Ethene
-
- @Elements in Group II are called:
- Alkaline earth metals
- Alkali metals
- Halogens
-
- @If you had one 10g lump of a substance, and ten 1g lumps of the same substance then:
- The ten 1g lumps would react faster
- The one 10g lump would react faster
- There would be no difference in the reaction rates
-
- @Copper II oxide reacts with hydrogen to form copper and water. The copper II oxide is:
- Reduced
- Oxidised
- Neutralised
-
- @Farmers must be very careful when adding nitrates (in fertilizers) to their land because:
- Nitrates are soluble and could contaminate water supplies eventually
- Lime in the soil reacts with the nitrates
- The soil can quickly become too acidic for crops to grow
-
- @Carbon monoxide is poisonous because it:
- Combines with the oxygen carrying portions of blood
- Is oxidised in the lung
- Produces carbon in the lungs
-
- @If you were asked to measure 21.7 cmÏ of liquid as accurately as posible, which one would you use?
- 50cmÏ burette
- 100cmÏ beaker
- 25cmÏ pipette
-
- @To separate large pieces of glass from water, what technique would be best?
- Decanting
- Dissolving, filtering and evaporation
- Sublimation
-
- @?HÛOÛ ï 2HÛO + O The number needed to balance the equation is:
- 2
- 1
- 4
-
- @The diagram shows part of a pH chart. Where abouts would lemmon juice go?
- #phscale
- Position n
- Position j
- Position k
-
- @The diagram shows a Hoffmann voltameter, connected to a power supply. The blue liquid is water, with a little sulphuric acid in it. The gas X is:
- #hoff
- Oxygen
- Hydrogen
- Sulphur dioxide