Acids and bases - Assignment PDF

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Chemistry Nes Topic: Acids and Alkalis 16 February 2020 Textbook Questions Pg 187 1a. Copper hydroxide, copper oxide,copper carbonate 1b. Copper oxide+sulfuric acid= copper sulfate+water Copper hydroxide= Copper sulfate+ water Copper carbonate=copper sulfate+ water+ carbon dioxide 2a. A= copper B= copper oxide C= Copper sulfate D= E= F= Worksheet Questions When metals react they form positive ions The more reactive a metal the more likely it is to form an ion Aqueous solutions of alkalis contain hydroxide ions Key term definitions

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Oxidation: Gain of oxygen or loss of electronsa Reduction:loss of oxygen or gain of electrons Redox reaction: Transfer of electrons between two chemicals, one goes through oxidation while another goes through reduction Alkali: from 8-14 on pH scale, a source of hydroxidde ions in solution Neutralistion: When acids and alkalis react together a solution is neturalised The pH scale goes from 0-14 Numbers of pH less than 7 are acidic pH 7 is neutral Numbers of pH above 7 are alkaline Name the salt produced when you use Hydrochloric acid= chloride Sufluric acid= sulfate Nitric acid= nitrate Hydrochloric acid+ sodium hydroxide→ sodium chloride+ water H+(aq) + OH → H2o (1) Magnesium+oxygen→ magnesium oxide zinc + oxygen→ zinc oxide Oxidation reactions sinxe they have lost electrons Calcium carbonate+ hydrochloric acid→ calcium chloride+ water+ carbon dioxide

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17th February 2020 Metal + acid→ salt + hydrogen Metal carbonate + acid→ salt + water + carbon dioxide acid + base→ salt+water Magnesium chloride Lead nitrate Copper sulfate Potassium chloride Salts made from hydrochloric acid are called chloride Salts made from sulfuric acid are called sulfate Salts made from nitric acid are called nitrate Salts made from phosphoric acid are called phosphate Metal+ acid→ hydrogen+salt Metal oxide+acid→ salt+water Metal hydroxide acid→ salt+water Metal carbonate acid→carbon dioxide+water+salt Lead and hydrochloric acid→ lead chloride Aluminium and sulfuric acid→ aluminum sulfate Zinc and nitric acid→ zinc nitrate

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Aluminium and hydrochloric acid→ aluminum chloride Magnesium and sulfuric acid→ magnesium sulfate Name of salt Zinc chloride Magnesium sulfate Lead nitrate Tin chloride

Common name of acid

formula

Salt name

Nitric acid

HNO3

Hydrogen nitrate

Sulfuric acid

H2SO4

Hydrogen sulfate

Hydrochloric acid

HCl

Hydrogen chloride

1. Lead oxide+sulfuric acid→ lead sulfate+ water 2. Nitric acid+sodium hydroxide→ sodium nitrate+water 3. copper + hydrochloric acid→ copper chloride+hydrogen 4. Potassium+nitric acid→ potassium nitrate+hydrogen 5. Sulfuric acid+ iron oxide→ iron sulfide+water Chemical equations 1. PbO+H2SO4→ PbSO4+H2O 2. HNO3+NaOH→ NaNO3+H2O 3. Cu+HCl→ CuCl2+H2 4. K+HNO3→ KNO3+H2 5. H2SO4+Fe2o3→ Fe(SO4)3

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Homework pH: a s scale used to show how acid/alkaline a solution is Neutral: a solution with a pH value of 7 which neither acid or alkali Alkali: its solution has a pH value more than 7 Bases: The oxide, hyrdoize or carbonate of a metal that will react with an acid forming a salt, proton acceptor (H+) Acid: When dissolved in water, its solution has a pH value less than 7. Acids are proton (H+ ion) donors Acids produce hydrogen ions in aquoeus solutions Aqueos solutions of alkalis contain hydroxide ions A solution with pH 7 is neutral Aqueous solutions of acids have pH value of less than 7 Aqueous solutions of alkali have pH values greater than 7 A pH scalee is an indication of how acid, alkali, or neutral a solution is. 1-6= acid , 7=nrutral, 8-14= alkali. pH of a solution can be measured using a universal indicator and then comparing with the c olors on a pH scale, itll tell you the pH of the solution

February 23 2020 Starter Acid: pH below 7, H+ ion Base:Anything that neutralizes acid

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Alkali: above pH 7, OH-, in solution Insoluble: can't dissolve in liquid Give an example of an acid: hydrochloric acid Give an example of an alkali: sodium hydroxide Example of a base: calcium carbonate Making soluble salt

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cation= metal ion

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anion = nonmetal ion

Zinc Nitrate= Soluble because nitrate Sodium carbonate= soluble because sodium Calcium carbonate= insoluble, carbonate Copper sulfate= soluble, sulfate Barium sulfate= insoluble, exception for barium sulfate 7

Iron bromide= soluble, because bromide is a halide Silver iodide= insoluble, silver Potassium hexacyanoferrate= soluble, potassium Ammonium carbonate= soluble because of ammonium

Making soluble salts ( from an insoluble base) -

Appropriate acid with base, carbonate, metal

Heat acid in water bath, speeding up reaction - Fume cupboard to avoid toxic fumes Add base to acid Wait until solid starts to sink to bottom, filter the excess solid to get solution of just salt + water Heat solution gently to evaporate off the water, leave solution to cool, let salt crystalize

Soluble salt from a soluble base

Making an insoluble salt

It's basically titration but you only use the indicator to know the volumes, and then do the experiment without indicator so it's not a contaminant

Perciptation reacts

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Use ‘pipette to add alkali to conical flask Add indicator to flask Use burette to add acid to conical flask Add acid drop by drop Swirl the contents of flask until it changes color Do the same thing with the same volume of acid and alkali but no solution= purely salt + water Evaporate off some water and leave solution to crystallise Filter off the solid and dry it - Left with salt

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Add two soluble solutions to another

Copper oxide + sulfuric acid→ copper sulfate + water

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hydrochloric acid sodium hydroxide Sodium chloride= salt (use phenophylen indicator)

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