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DO NOW!!. How would you write the name of the following compounds Zn(OH) 2 NaOH HCl Mg(NO 3 ) 2 What does an acid do to red litmus? What does an acid to do blue litmus? How can we tell the pH of a substance?. Review. Ions – table of ions open in work book Flame test.
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DO NOW!! • How would you write the name of the following compounds • Zn(OH)2 • NaOH • HCl • Mg(NO3)2 What does an acid do to red litmus? What does an acid to do blue litmus? How can we tell the pH of a substance?
Review • Ions – table of ions open in work book • Flame test
Common examples? Everyday Life ACIDS: Tartaric acid Citric acid DNA Carbonic acid BASES: Magnesium hydroxide Limestone Garden lime Baking soda The Lab ACIDS: Hydrochloric acid – HCl Nitric acid – HNO3 Sulfuric acid – H2SO4 Ethanoic acid – CH3COOH BASES: Sodium hydroxide – NaOH Potassium hydroxide – KOH Calcium hydroxide – Ca(OH)2 Ammonia – NH3
Neutralisation • When an acidic solution is mixed with an alkaline solution a NEUTRALISATION reaction occurs H+ ions in acid, react with OH- of the base forming water H+ + OH- H2O
Example: HCl solution – mixed with NaOH Some H+ reacted not all – solution still acidic Complete neutralisation when all the H+ have reacted with OH- FINAL SOLUTION WILL CONTAIN Na+ and Cl- ions – evaporation = NaCl crystals
To Do: • In your lab group • At least 8 test tubes • Two beakers • Universal Indicator • Test tube rack • Challenge: Create the best looking rainbow of pH using your acids (HCl) and base (NaOH) • Use the neutralisation reaction
DO NOW!! • Acid + Base = ??? • What is an ionic compound? • When writing ionic formula does the metal change its name of the non-metal?
DO NOW • Acid + Base = ???? + ???? • Write the salts formed from the following reactions (word equation) • Sulfuric Acid + Sodium Hydroxide • Hydrochloric acid + Potassium Hydroxide • Nitric Acid + Sodium Hydroxide • Write ionic formula for the salts produced • ION QUIZ
Reaction 1 - Neutralisation ACID + BASE → SALT + WATER e.g. hydrochloric acid + sodium hydroxide → sodium chloride + water HCl + NaOH → NaCl + H2O e.g. sulfuric acid + potassium hydroxide → potassium sulfate + water H2SO4 + KOH → K2SO4 + H20 2
Which salt is made? • Nitric acid + Sodium hydroxide • Sulfuric acid + Potassium hydroxide • Hydrochloric acid + Magnesium oxide • Ethanoic acid + Sodium hydroxide Sodium nitrate Potassium sulfate Magnesium chloride Sodium ethanoate
Reaction 1 - Neutralisation ACID + BASE → SALT + WATER Question: What sorts of compounds act as bases in this case? Answer: Metal oxides and metal hydroxides MgO CuO Fe2O3 ZnO Mg(OH)2 Cu(OH)2 Ca(OH)2 NaOH KOH
Equations (1) Hydrogen chloride + Magnesium oxide → Magnesium chloride + Water 2 HCl + MgO→ MgCl2 + H2O (2) Nitric acid + Sodium hydroxide + → Sodium nitrate + Water HNO3 + NaOH→ NaNO3 + H2O (3) Sulfuric acid + Calcium hydroxide → Calcium sulfate + Water 2 H2SO4 + Ca(OH)2→ CaSO4 + H2O
More neutralisation reactions 1. Hydrochloric acid + Zinc oxide → Zinc chloride + water 2. Nitric acid + Copper oxide → Copper Nitrate + water 3. _____ + Sodium hydroxide → Sodium sulfate + water 4. Hydrochloric acid + Iron oxide → ___________ + water
More neutralisation reactions 1. Hydrochloric acid + Zinc oxide → Zinc chloride + water HCl + ZnO→ ZnCl2 + H2O 2 2. Nitric acid + Copper oxide + → Zinc nitrate + water 2 HNO3 + CuO+ → Cu(NO3)2 + H2O 3. Sulfuric Acid + Sodium hydroxide → Sodium sulfate + water H2SO4 + NaOH→ Na2SO4 + H2O 2 2 Iron chloride 4. Hydrochloric acid + Iron oxide + → ___________ + water 3 HCl+ Fe2O3→FeCl3+ H2O 6 2
Useful neutralisation 1. Antacid (“anti-acid”) tablets • Stomach acid (HCl) causes heartburn • “Quick-eze” contain a base, magnesium hydroxide - Mg(OH)2 • The base neutralises the stomach acid, relieving the symptoms of heartburn Hydrochloric acid + Magnesium hydroxide → Magnesium chloride + water
Useful neutralisation 2. Toothpaste and tooth decay Bacteria on our teeth produce acids as part of their metabolism The acid wears away the enamel on our teeth Toothpaste is basic, this helps to neutralise the acid and prevent tooth decay
Past exam paper: Epsom salt has the chemical formula MgSO4. It can be prepared by reacting an acid with magnesium hydroxide Give the chemical name for MgSO4 Name the acid used in this reaction Write the word equations for the preparation ofMgSO4 This reaction is described as a neutralisation reaction: Explain what is meant by neutralisation reaction
Past exam paper: Epsom salt has the chemical formula MgSO4. It can be prepared by reacting an acid with magnesium hydroxide Give the chemical name for MgSO4 Magnesium sulfate Name the acid used in this reaction Sulfuricacid Write the word equations for the preparation of MgSO4 Magnesium hydroxide + sulfuric acid = magnesium sulfate + water This reaction is described as a neutralisation reaction: Explain what is meant by neutralisation reaction
Bingo 1. H+ 2. red 3. litmus 4. atomic number 5. ion 6. metal 7. CO32- 8. NO3- 9. sulfate 10. sulfuric acid 11. Sodium hydroxide 12. alkali 13. base 14. OH- 15. positive 16. CH3COOH 17. (NH4)2CO3 18. negative 19. HCO3- 20. Al2O3
Acids and carbonates ACID + CARBONATE → SALT + WATER + CARBON DIOXIDE e.g. Hydrochloric acid + Calcium carbonate → Calcium chloride + water + carbon dioxide NB – This also occurs with BICARBONATES (Hydrogen carbonates) Acids and metals ACID + REACTIVE METAL → SALT + HYDROGEN GAS e.g. Sulfuric acid + Magnesium → Magnesium sulfate + hydrogen
Acids and carbonates 1. Hydrochloric acid + Calcium carbonate → Calcium _____ + water + CO2 2. Nitric acid + Copper carbonate → Copper _____ + water + CO2 3. Sulfuric acid + Sodium carbonate → Sodium _____ + water + CO2 4. Ethanoic acid + Zinc carbonate → Zinc _____ + water + CO2
To Do: • Below is an example of what? Blue is for.... Red is for... • Acid + Carbonate -- • Write the colour changes when copper carbonate was heated.
Heating Carbonates • Exam question in the past • Heat Copper carbonate in a test tube • Heat till colour change • Add Sulfuric Acid (up to first article) • Filter • Solution we will leave to evaporate so put in evaporation dish • Clean Up
Useful carbonate reactions Baking powder This contains baking soda (sodium hydrogen carbonate) and anacid (usually tartaric acid) in powder form. When the baking powder is added to water, the baking soda and the acid react, producing CO2 gas and making the cake rise!
Useful carbonate reactions Fizzy tablets – like Berocca These contain an acid and a carbonate in powder form When the tablet gets wet, the acid and carbonatereact together to form CO2 – the fizzy bubbles
Useful carbonate reactions Limestone caves: Limestone is composed ofcalcium carbonate Caves form when acidic rainwaterdissolves the limestone, formingcracks and fissures The limestone reappearsunderground as stalactites andstalagmites
Today: • Acid + Carbonate demo • Equations from the experiments (EVERYONE NEEDS TO GET!!) Mark using marking sheet Once finished: Mind map of atoms and acids and bases topic Team Quiz