Survival chemistry For Us All (Oxidation and Reduction)

Interactive Version

An adventure through one of the most frequently complaint as hard to learn chapter in form 5 Chemistry syallabus… Oxidation & Reduction

This is a interactive slide show. It is a thorough guide through the hard copy of the book entitle „Survival Chemistry For Us All‟. Basically all you have to do is to follow the whole story and decide which path to take. Click on the button beside the statement after each paragraph and see how brilliant you are in „Oxidation and Reduction‟. Good Luck. To proceed, kindly click on the button beside. GO

Your name is Dr Niles Thompson and you are a great friend of Princess Lisa, daughter of the king of Grandville. Due to the intelligence you posses in Chemistry, Princess Lisa brought you to see her father as he is in need for the best Chemist in the country .This is a very important mission so every step or decision you make can change the fate of the country drastically and your fate as well. The king would not stop questioning you about almost everything as that is his way of searching. So be patient. GO

You met Princess Lisa. She sees your keenness on the project. Hence, she brought you to the king. The king asks you whether you are well prepared to take the challenge. You nodded. He then asks you what a redox reaction is. If you answer „It is a reaction involving oxidation/reduction only,‟ GO If you say „It is a reaction involving both oxidation and reduction,‟ GO

The king shook his head. You disappoint him. You failed to even begin. Go through note once again and start again. GO

The king smiled broadly. Your mission begins. GO

In the first meeting prior to the beginning of your mission, the king brought you to his fruit garden. There are plenty of ripe apples. The apples are cut and served. Both of you chatted for half an hour. When the conversation ended, the apples changed colour. The king curiously asked you what happened to the flesh of the apples. If you answer „the apples had oxidised,‟ GO If you answer „the apples had been reduced,‟ GO

The king looked at the apples and asked you again. When oxidation happens? If you answer when apple gains oxygen, GO If you answer when apple loses oxygen, GO

The King paused and he threw the apples to you all at once. It meant you failed. Start again. GO

The king asks you if the gain of hydrogen and electrons are oxidation. If you say TRUE, GO If you say FALSE, GO

The king shouted at you as you made him confused. You have not mastered the basics of this chapter. You failed. Try again from the start. GO

The king nodded. He handed you a bunch of keys. Keep note on that. You passed the first day. Well done. Proceed. GO

On day 2, the king brought you to a lab situated not to far away from the castle. The king instructed you to open the door. He handed you a thick and dusty old proposal. “Look through it and buy some appropriate materials for each experiments.” He called you to look into it and prepare for the first experiment. He will come back to check on you later. When the king left, you flipped to page 1 of the proposal. (See page 55) You need to buy a big mass of reducing agent. If you approve to buy carbon powder, GO If you approve to buy copper powder, GO

The materials you bought were here on time. The king wants you to demonstrate in front of him right away and at last to determine which metal can be used to extract the zinc oxides from a source. You used carbon powder in the experiment. As you predicted, reaction occurred. The king smiled. He asks you why carbon is a reducing agent. If you answer „because carbon reduces zinc powder from zinc oxide,‟ GO If you answer „because carbon reduces itself to become carbon dioxide gas,‟ GO

The king said you are not prepared. Start again. GO

When you used copper powder in the experiment, you demonstration in front of the king failed as no reaction occurred. You carelessly brought the wrong reducing agent for the experiment. The king is mad at you. You failed. Better luck next time. GO

The King said right after the demonstration that he wants you to tell him the colour changes of the metal produced when it is hot and when it is cooled. If you answer orange when hot and yellow when cold, GO If you answer yellow when hot and white when cooled, GO

The king said you are Colour Blind. You failed, start again. GO

The king called you to keep the zinc powder obtained in a container for the next experiment. Your job for today is done. Day 3, Proceed. GO

You are called to look at page 56 to read through experiment 2. This time you‟re on your own. Although you are not observed by the king, you have to do your very best as there will be a spy watching you. You need to find out which metal is above the other. With the given material, predict the position of the metals. If you write „zinc is above copper‟ in you report, GO If you write „copper is above zinc‟ in your report, GO

When the report was proposed in front of the king, he is satisfied. He rewarded you with an iron token. You are told to keep the iron made token safely and carefully so that it will not be damaged or rusted. You can either choose to keep it on your book rack for display, or inside your science lab, somewhere near the sink. Wherever you choose, kindly jot down and never change your stand. Your job for today is done. Proceed. GO

The king became angry the minute he read your report. He called you to go home and never come back. You failed. Start again. GO

Another day begins. The king brought Princess Lisa with him to observe you. Princess Lisa wants to see some experiments involving colour change as she likes colours. You flipped through the book of experiments and decided to show her experiment 3 (look at page 57). You gathered the materials and appropriate apparatus for the experiment. However, you thought for a while. You asked yourself which reagent is a reducing agent and which reagent is an oxidising agent. If you tell yourself that zinc powder is the reducing agent while chlorine/bromine water is the oxidising agent, GO If you tell yourself that chlorine/bromine water is the reducing agent while zinc powder is the oxidising agent, GO

You drop bromine water drop by drop into a test tube filled with 2cm3 of iron (II) sulphate solution. Then you divide the solution into 2 test tubes. The redish brown bromine water becomes colourless. The green colour of iron (II) sulphate becomes brown. Test tube A you tested it with sodium hydroxide solution while test tube B you tested it with potassium thiocyanate. Test tube Observation A Brown precipitate formed. The precipitate is insoluble in excess sodium hydroxide solution. B The solution turns deep red. The Princess was fascinated. She checked the colour changes with the written report and smiled because you did it correctly. She asks you what happened to iron (II) ions. If you answered „it is oxidised into iron (III) ions‟ GO If you answered „it is reduced into iron (III) ions‟ GO

You put a spatula of zinc powder into a test tube filled with 2cm3 of iron (II) sulphate solution. Then you divide the solution into 2 test tubes. There were no changes. You carried on. Test tube A you tested it with sodium hydroxide solution while test tube B you tested it with potassium thiocyanate. Test tube Observation A Green precipitate formed. The precipitate is insoluble in excess sodium hydroxide solution. B The solution turns pale red. “Let me have a look,” said Princess Lisa. GO

She checked the colour changes with the written report and frown because you did it incorrectly. You failed. Start again. GO

You carried on the second half of the experiment by putting one spatula of zinc powder into a test tube containing 2cm3 of iron (III) sulphate. You stirred it with a stirring rod. The zinc powder dissolves. The brown colour of iron (III) sulphate solution turns light green.The excess zinc powder is filtered out. Then you divide the filtrate into two test tubes. Test tube A you tested with sodium hydroxide solution. Test tube B you tested with potassium hexacyanoferrate (III). Test tube Observation A Green precipitate formed. The precipitate is insoluble in excess sodium hydroxide solution. B The solution turns dark blue (bull blue) Princess Lisa checked again. You got it right again. Well done. Before she leaves to see her father. She asks you what had happened to iron (III) ions. If you answer „it is oxidised into iron (II) ions, GO If you answer „it is reduced into iron (II) ions, GO

You are right. This time you obtained a merit from the king. He likes you. Another day was over, Proceed. GO

You gave the wrong explanation. Sorry start again. GO

Princess Lisa shook her head. She said the reason you succeeded in doing this experiment was because of luck thus, you failed. Try again. GO

Today is your lucky day as you do not have to do the experiment yourself. All you have to do is watch, predict and answer the questions by the king. You entered the lab early to view the experiment (look at page 58) If you have any doubt, simply view the reactivity series of metal beforehand on NOTES When the king entered the lab, your mission begins. By looking at the materials used, the king asks if there will be any sparks produced or any strongly glow of burnt metal when copper is burnt in excess oxygen. If you answer YES, GO If you answer NO, GO

The king said you are lack of preparation. He forgives you this time but you have to start again on the day. This time read more. GO

The king proceeds. He calls you to rearrange the metals according to decreasing reactivity of metals towards oxygen. What are the missing two metals? (Refer to what metal you have in your experiment) Magnesium x Iron y Copper If you answer x= zinc; y=lead, GO If you answer x= lead; y=zinc, GO

The king later wants you to tell him the colour of lead oxide when hot and when cool. If you answer orange when hot and yellow when cooled GO If you answer yellow when hot and orange when cooled GO

The king forgives you. You must start again on the day. GO

Wow, you impressed the king. Today is done. Proceed. GO

Oh no, the king is mad... he calls you to leave. Start again from the day you received the token. GO

Day 5 begins. The king asks you if you remembered how to determine the empirical formula of copper (II) oxide. If you remember, that is the way of conducting experiment 5. You read through page 59. The king suddenly asks you how to prepare dry hydrogen gas for the experiment. Method 1: Sulphuric acid + zinc granules (the gas is channelled through anhydrous calcium chloride.) Method 2: Sulphuric acid + zinc oxide (the gas is channelled through anhydrous calcium chloride.) If you used method 1 GO If you used method 2 GO

The king wants you to tell him which metal oxide can be reduced by hydrogen gas. If you answer copper oxide GO If you answer zinc oxide GO

“Are you sure?” he asks. He shook his head. Start from checkpoint. GO

He calls you to rearrange the metals according to decreasing reactivity of metals towards hydrogen. What are the missing two metals? (Refer to what metal you have in your experiment) Hydrogen Iron x y Copper If you answer x= tin; y=lead GO If you answer x= lead; y=tin GO

The king is disappointed by you. Try again from the day you obtained the token. Checkpoint. GO

The king is happy. He wants you to bring your token along to celebrate the beginning of the big day tomorrow. You can rest for now. Proceed. GO

The king sighs. You failed last minute. Too bad. Start from the day you obtained the token. Checkpoint. GO

Today is your big day as you finally have the chance to lay your hands upon the vital project- The bridge of Grandville that will link Grandville to another country. This bridge can aid in the economic growth of Grandville so you must make sure that it does not rust or get damaged so easily. Remember where you placed your token? If you chose to keep it on your book rack for display GO If you chose to keep it inside your science lab, somewhere near the sink GO

So you managed to pass the kings hidden crucial test as your iron made token did not rust. Your important mission begins. Proceed. GO

Sorry to say but you failed as your iron made token rust this showed how badly you are in choosing the right condition for protecting an iron made object from rust. Start again, you shall. GO

Now, the king assigned you to work with fellow engineers and architects on the project. You need to start from scratch. You have to conduct and experiment to determine which metal can help to prevent the iron bridge from rusting. Because there were no alloys invented at that period of time, you have no choice but to build the bridge using iron. The experiment you have to conduct is also in the book of experiments on page 60. By conducting the experiment, you know that metal which are more electropositive can help to prevent iron from rusting. The king later calls you to buy in appropriate metal to be the sacrificial metal. If you choose zinc, GO If you choose tin, GO

The king instructed the engineers to attach some tin metal onto the miniature iron bridge. After a few days, the miniature iron bridge exposed to air and water is damaged as it rusted. You failed. Sorry, start again from page 20 if your token dust not rust GO start again from the beginning if your token rusted. GO

The king instructed the engineers to attach some zinc metal onto the miniature iron bridge. After a few days, the miniature iron bridge exposed to air and water is still in perfect form. You succeeded in the choosing process. A few months later, the bridge builds after your name called „the bridge of Niles‟ has completed. You are made the hero of the country. You saved the economy, science and technology of Grandville. Well done! Chemistry isn‟t that tough after all! Proceed to next page. GO

Thank you for trying out the adventure. Hopefully this will help you in the chapter of oxidation and reduction. If you have any comments about the book or you would like to post a question, kindly log on to http://survivalchemistry.blogspot.com/

“If that can help in scoring Chemistry, we should try that sometimes...” End

The Book of Experiments Proposed by Dr Hans Richard Experiment 1: Extraction Materials: Carbon, Zinc oxide, Iron, Tin, Silver, copper. Apparatus: pipe clay triangle, Bunsen burner, tripod stand, crucible, spatula Back

Experiment 2: Displacement Materials: Zinc powder, Copper powder, zinc sulphate solution, copper(II) sulphate solution. Apparatus: Spatula, test tube, measuring cylinder. Back

Experiment 3: Iron ions Materials: Filter paper, Iron (II) sulphate solution, iron (III) sulphate solution, potassium hexacyanoferrate (III), potassium thiocyanate, bromine and chlorine water, zinc powder, sodium hydroxide solution. Apparatus: Test tubes, test tube holder, filter funnel, dropper, spatula, measuring cylinder. Back

Experiment 4: Metal Vs Oxygen Materials: Magnesium powder, zinc powder, iron powder, copper powder, lead powder, potassium manganate (VII) crystals, glass wool, asbestos paper. Apparatus: Boiling tubes, retort stand, Bunsen burner Back

Experiment 5: Metal Vs Hydrogen Materials: zinc granules, dilute sulphuric acid, copper (II) sulphate solution, anhydrous calcium chloride, zinc oxide, iron (III) oxide, copper (II) oxide, asbestos paper, wooden splinters, lead (II) oxide. Apparatus: Flat bottomed flask, thistle funnel, delivery tubes with rubber stopper, U-tube, combustion tube with a small hole at the end, retort stand, Bunsen burner. Back

Experiment 6: Metal protecting iron Materials: Iron nails, magnesium ribbon, zinc strip, tin strip, copper strip, agar-agar solution mixed with potassium hexacyanoferrate (III) and phenolphthalein indicator. Apparatus : sand paper, test tube, test tube racks. Back

One stop HELP Oxidation is the: *Gain of oxygen *Lose of Hydrogen *Lose of electron *Increase in oxidation number Reduction is the: *Lose of oxygen *Gain of Hydrogen *Gain of electron *Decrease in oxidation number Redox Reaction *A reaction in which oxidation and reduction occur at the same time

Oxidizing Agent *Oxidizes a substance. It is reduced in the redox reaction Reducing Agent *Reduces a substance. It is oxidized in the redox reaction Oxidizing agent Reducing agent Acidified potassium manganate(VII) solution , KMNO4 Chloride ion, Cl- Acidified potassium dichromate(VI) solution, K2Cr2O7 Bromide ion, Br- Chlorine water, Cl2(aq) Iodide ion, I- Bromine water, Br2(aq) Sulphate (IV) ion, SO42- Iron (III) ion, Fe3+ Sulphur dioxide, SO2 gas Hydrogen sulphide, H2S Oxidation Number/ Oxidation State *The imaginary charge of an atom if it exists as an ion

Corrosion of a Metal *The oxidation of the metal through the action of water, air, and/or electrolytes Rusting of Iron, Fe *The corrosion of iron, Fe. It is a redox reaction in which iron, Fe is oxidized to form hydrated iron (III) oxide, Fe2O3.3H2O or rust Reactivity Series of Metals *An arrangement of metals in the order of their reactivity towards oxygen, O2 Vigour of a Chemical Reaction *Shows how reactive the reaction is The Extraction of Metal *The process of obtaining a metal from its ore Electrolytic Cell *An electrochemical cell that uses electricity to produce a chemical change Chemical/ Voltaic Cell *An electrochemical cell that produces electricity from a chemical change

Reactivity Series of metal K Special techniques: Na Ka-lium-Na-trium-Mag-ne-si-um, Mg A-lu-mi-nium-Car-bon-Zinc, Al Hy-drogen-Fe-rum-Sta-num-Plum-bum, C Cop-per-Mer-cury-Sil-ver-Gold. Zn H *Try reading them like raping and clap your Fe hands as beat. If you can rap, so can you Sn memorize this! Pb *The underline section is where you clap while Cu the bold alphabets are the symbols. Hg *Note that the last four has special symbol, Ag different from the name of its element. Au

Electrochemical Series of Metal K Na Ca Mg Special Techniques Al *Try memorizing the series by singing. Zn *Use the elements as the lyrics while the tune to blend. Fe *Try using tune: Twinkle Twinkle Little Star Sn Pb H Cu Ag Au

Twinkle twinkle little star, -Ka-lium Na-trium Cal-ci-um- How I wonder what you are, -Mag-nesium Alu-minium Zinc- Up above the world so high, -Fe-rum Sta-num Plum-bum- -Hydrogen?- Like a diamond in the sky, -Cu-prum Agen-tum Au-rum- Twinkle twinkle little star, -Po-tassium So-dium Iron Tin- How I wonder what you are. -Lead Cop-per Sil-ver Gold-

Experiments -Change of iron (II) ions to iron (III) ions and vice versa -Displacement of metals -Displacement of halogens -Transfer of electrons at a distance -Effects of other metals on rusting of iron -Reactivity series of metal with oxygen -The position of carbon in the reactivity series of metal with oxygen -The position of hydrogen in the reactivity series of metal with oxygen -Oxidation and reduction in electrolytic cells/Chemical cells *Note that the ones bold is not mentioned in this book. Kindly refer to other references as these are the experiments needed to be mastered for Chapter 3 Form 5 – Oxidation and Reduction. Back

Survival chemistry For Us All (Oxidation and Reduction)

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