what is filtration used for, for salt | Filtration can be used to separate an insoluble solid from a liquid. |
how can we test for zinc | adding dilute sodium hydroxide or ammonia solution which will make a white precipitate, but with excess sodium hydroxide the precipitate becomes a colourless solution. |
the pH scale values, what does 0 - 7 pH mean | acidic - neutral |
the pH scale values, what does 7-14 pH mean | neutral - alkali |
what happens when a acid is placed on blue litmus paper | the litmus paper will turn red. |
what happens when a acid is placed in methyl orange indicator | it will turn red |
what can acids neutrlise | a base, forming salt and water |
what happens when acids react | they lose electrons and form positively charged hydrogen ions. This is what makes it acidic. |
what does acid react with to make salt and hydrogen | Acids react with metals to make a salt and hydrogen. The name of the salt is related to the name of the acid used i.e. sulfuric acid will make sulphate. |
acids can react with bases to make what.... | Acids react with metal oxides and metal hydroxides (bases) to make salt and water, neutralising the substance. |
acids react with carbonate to make what | Acids react with metal carbonates to make a salt, carbon dioxide and water. |
what is a base | A base that is water-soluble is called an alkali |
what happens when a base is placed on red litmus paper | the litmus paper will turn blue. |
what happens when a base is placed in methyl orange indicator | it will turn yellow |
what can bases neutrolise | Bases can neutralise acids, forming a salt and water. |
what are bases normally | oxides or hydroxides of metals. |
when bases react they.... | When bases react they gain electrons to form negative hydroxide ions, OH- |
what do bases react with to make salt and water | acids |
bases + ammonium salt = | Bases react with ammonium salts to form a salt, water and ammonia. |
what is bases + ammonium salt (what reaction) | This is a decomposition reaction using heat. |
what is bases + ammonium salt also used to test for something | This reaction is also used as a test for the ammonia ion (NH₄+) |
what can be used to neutroalise the soil | Powdered limestone, lime or slaked lime can be carefully used to neutralise the soil. |
what are acids | Acids are proton donors as they ionise in solutions creating protons which are practically H+ ions, which make the solution acids. |
what are bases | Bases are proton acceptors as they ionise in solutions creating OH- ions, which makes the solution alkaline. |
what are oxides | Oxides are metals or non-metals that have reacted with oxygen. |
most metal oxides are basic meaning | They do not react with alkalis. |
most metal oxides are basic meaning... | Many basic oxides do not react with water. But those from group 1 and 2 do react with water to make metal hydroxides. |
most non metal oxides are acidic meaning.... | They react with alkalis to form salt and water. |
most non metal oxides are acidic meaning.... | Some acidic oxides react with bases when heated to make salts. |
most non metal oxides are acidic meaning.... | Many acidic oxides react with water to form acidic solutions. |
some oxides are neutral meaning.... | they don’t react with acids or bases |
some oxides are amphoteric meaning.... | they react with both acids and bases. |
what is distillation used for, for salt | Distillation can be used to separate the liquid and salt from a solution. |
what is filtration used for, for salt | Filtration can be used to separate an insoluble solid from a liquid. |
what is crystalation used for, for making crystales | by evaporating to make a lower volume of liquid which is then left to cool and then crystals are formed and consequently filtered out to get the crystals. |
how can we test for ammonia | adding dilute sodium hydroxide and heating it, which if ammonia is present, will create a pungent smell and will turn red litmus paper blue |
how can we test for copper (II) | adding dilute sodium hydroxide or ammonia solution which will make a blue precipitate. |
how can we test for calcium (II) | adding dilute sodium hydroxide or ammonia solution which will make a white precipitate. |
how can we test for iron (II) | adding dilute sodium hydroxide or ammonia solution which will make a pale green precipitate. |
how can we test for iron (III) | adding dilute sodium hydroxide or ammonia solution which will make a red-brown precipitate. |
how can we test for zinc | adding dilute sodium hydroxide or ammonia solution which will make a white precipitate, but with excess sodium hydroxide the precipitate becomes a colourless solution. |