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Why doesn't electrolysis always undergo the reactions predicted? I know about electrolyste concentration, gas pressures, what electrodes are, current, voltage, but I don't know how they impact, except for concentration, I think. With the voltage one, should the voltage be much, much higher than...

1. An experimental source of power for a heart pacemaker involves implanting a zinc electrode and a platinum electrode into tissues in the body. Oxygen present in body fluids is reduced at the platinum electrode. Before this method of power generation if used, what further investigations would...

I'm just a little confused about this topic. I understand the thinking process when working out these problems, or by drawing tree diagrams and such, just dont know how to use the formula P(A given B)= P(A intersecting with B)/ P(B). Working out P(A intersecting with B) is a problem because...

This question is confusing, because drawing all over the table of standard potentials didnt work. A student carries out experiments with four reductants, H2, P, Q and R. metal Q reacts with a solution of PSO4 to produce metallic P. gaseous hydrogen will reduce cation R2+ and and one other...

Several pressing questions :) I was told by one person that it wouldn't matter if the cells aren't under standard conditions (when doing experiment). I've read that the the order in the electrode potentials table can change if you don't! =S Eg. for a particular cell which half cell you connect...

1. A student working in the laboratory spilled an iodine solution over the bench, causing a dark brown stain to form. Suggest how the student could remove the iodine stain. Suggest how the student could remove the iodine stain. I am aware you would probably go and pour something over it to...

A 0.254g sample of black coal was burnt in a bomb calorimeter. The calorimeter contained 300ml of water which rose from 19.25C to 24.92C a) Using the specific hat capacity of water, calculate the heat of combustion of the coal ... which i've done b) Is your answer likely to be higher or lower...

Some random questions I was wondering whether someone could help me out with: 1. A hand-warmer purchased by campers and skiers consists of a sealed outer plastic bag and an inner perforated plastic bag containing powdered iron, water, salt and sawdust. When the inner bag is taken out and shaken...

Two questions which I figured out I couldn't figure out how to do (they dont look hard, though :bomb: ) A sample of 1.00g of a pesticide is analysed for its arsenci content by precipitation of the arsenic as the sulfide, As2S3. If 0.123g of the sulfide is obtained, the percentage by mass of...

Some quick urgent questions: Oxidising CH3CH2OH to CH3COOH... Cr2O7(2-)/MnO4- (these are meant to be above the arrow) CH3CH2OH(aq) ----> CH3COOH(aq) H+(aq) Why does the oxidant, eg. acidified potassium dichromate, have to be...

Some evil questions I came across: 1 Explain why ethane, the feedstock used in the thermal cracking process, is present among the products and suggest what would be done with this substance. 2 What are the main reasons why the clustering of companies in the Altona Complex is commercially...

We did an experiment with the equliibrium: Co2+(aq) + 4Cl-(aq) <---> CoCl4(2-) (aq) Co2+(aq) is pink (I'm guessing it's hydrated crystals in solution, 'cause anhydrous CoCl2 is blue?), Cl-(aq) is colourless, CoCl4(2-)(aq) is blue. Basically, we did 3 tests. Test A: Temperature change. Test...

An urgent question, but when you're talking about the effects of temperature on an equilibrium, any, say, H3PO4(aq) <---> H2PO4-(aq) + H+(aq) (exothermic), is it wiser to talk about it in terms of the increasing and decreasing of K values, or the shifting of the equilibrium position? Eg. If you...

NaOCl is completely dissociated in water to form Na+(aq) and OCl-(aq). In solution OCl- hydrolyses according to the equation OCl-(aq) + H20(l) <---> HOCl(aq) + OH-(aq) 100ml of pure water at constant temperature is added to a 100ml solution of 0.10M NaOCl. When the solution reaches...

Some questions: 1. If you were designing a sulfuric acid plant, briefly list important factors that you would consider when deciding: a. Whether to use powdered sulfur from a local supplier or molten sulfur transported a greater distance Cost of transport? b. If sulfur were to be burnt in...

URGENT... with acid reactions such as, say... acid + metal ---> salt + H2 or acid + metal carbonate ---> salt + CO2 + H20 How would you measure the rate of these types of reactions? I can think of some, like measuring the volume of gas evolved over time, or measuring loss of mass over...

Just needed a little explanation of concepts. Is the ionisation constant/product of water (Kw) like K in that it tells you the extent the reaction progresses? So... this reaction: H20(l) + H2O(l) <---> H3O+(aq) + OH-(aq) ionises very little? (Kw= 1.0*10^-14 at 25C) When you get water like...

I am having trouble with several questions: 1. Solutions of the acid-base indicator methyl red contains an equilibrium mixture of the red-coloured acid form of the indicator and a yellow-coloured conjugate form of the indicator and a yellow-coloured conjugate base form. The equilibrium can be...

In a question, I came across this graph: y= sq. root of-3(4-x) I graphed it on my calculator, and it didn't come up as I expected. It appears to have been dilated by sq. root of 3 parallel to the y-axis, then translated 4 units to the right. What happened to the two reflections? Reflection in...

Quick question. The equilibirium constant for the reaction given by the equation: 2HI(g) <---> H2(g) + I2(g) is 48.8 at 455C. An equilibrium mixture in a 2.0L vessel at this temperature contains 0.200mol of H2 and 0.100mol of I2 a. Calculate the concentration of HI in this mixture Hmm... is...