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Yes, ethanol with propanoic acid will yield an ester with a fruity odour like pineapples. This ester will have a boiling point of 99oC. Use an excess of the propanoic acid. Keep the heating mantle or the hot water bath at about 60 - 70oC. If you run short of time, then raise the temperature. You...

Metals Activity Series. A certain metal (solid) will displace Cu2+ ions, Ag+ and Sn2+ ions. It does not displace Zn2+ ions. Therefore we look up the activity series of metals, and we discover that metal M is probably iron or nickel, because only these two metals have a standard reduction...

Question 1. In order to measure the energy to separate one electron from an atom, you have to eliminate all the other variables that could influence the energy of the original neutral atom and the ions that are produced. That means there can't be any solvents, or any metallic bonds, or or any...

OK, full refluxing is a slow process. Make sure you do a proper risk assessment on the flammability of the chemicals. Make sure you have permission to leave the apparatus overnight, because to get a reasonable yield you are going to need 12 hours refluxing time. Make sure you have permission to...

Are you going to do a full reflux reaction to produce a pure ester, or are you just going to react in a test tube and describe the odour of the ester?

"The Volaré". The chairs are suspended on ropes or cables and they swing around in circular motion. The angle that the cables make is determined by the balance of forces on the chair. Weight force down, tension force in the cables supplies the centripetal force on the chair. You must design a...

That's a good question. There is insufficient information to rule that out. The student probably shouldn't assume there is no Zn in the soluble salts. They are probably doing Year 11 Chemistry, and they are probably up to Module 2, "calculate percentage composition'. I would expect the teacher...

Well, there are lots of possible approaches to determine the percentage by mass of zinc in such a mixture. I presume that is what you are being asked to do. Are you actually going to do this, or are you just designing the method? Easiest Method. ZnCO3 is almost insoluble in pH 7 water at room...

Have a look at that speed ... 1.25 x 108 m/s is 41.6 percent of the speed of light. That should alert you straight away. You are going to need the mass dilation equation. By the way, the radius of the proton path is measured in the stationary frame of reference of the observer and the...

It sounds like you are doing Module 7 The Nature of Light and you are up to the dot point about : "Investigate how the spectra of stars can provide information on: - surface temperature - rotational and translational velocity - density - chemical composition" The syllabus does not require...

All the above are good suggestions. For diagrams, don't forget there is always good old Microsoft Word shapes. Word contains a pretty comprehensive library of pre-built shapes, together with 'sticky' connectors and arrows that stay connected to the shapes. You can do grouping, layering and...

Calculating the Molar Enthalpy of Combustion of a variety of fuels is a classic first-hand investigation in Chemistry. It usually goes for about five minutes or until a reasonable mass of the fuel has been combusted, so that students can accurately calculate the moles of fuel that has been...

Ha ha. This question goes right back to Einstein's two postulates of special relativity. There is no privileged inertial frame of reference in the Universe that can be considered 'stationary'. Not the Earth, not our Solar System nor any other frame of reference. All objects are in relative...

In general, there is no connection between the equilibrium constant Keq and the rate at which a reaction converges to equilibrium. Therefore I consider the question to be invalid. I am happy to hear alternative arguments. However, as an interesting aside, we can state that the equilibrium...

Yes, calcium sulfate is roughly twice as soluble as calcium hydroxide. Actually the question contains a glaring mistake, which I will come to later. Let's talk about the addition of calcium nitrate. In a situation of competing equilibria, between precipitation of the hydroxide or precipitation...

The short answer is because parts (a) and (b) are irrelevant to part (c). That's why you can't use (a) or (b) to answer (c). Here is a partial solution to (c), see if that helps.

To atomise a molecule we have to break it up into individual atoms. OK, so categorise the bonds, and count the bonds. There are four C-H covalent bonds and one B-B covalent bond. Can you answer the question now?

Ahh ... no that's not the answer. It is about -284 kJ/mol

HINT: To derive the enthalpy of formation of C2H5OH (ethanol) we need a chemical equation that has the elements carbon, oxygen and hydrogen on the left-hand side in their standard states, and C2H5OH on the right-hand side. This chemical equation would have zero enthalpy of formation on the...

Always leave the rounding to the final result. Never round the intermediate results, or else you are introducing rounding errors half-way through the calculation. If you are answering a multi-part question, then the intermediate results can be reported after rounding, but when you carry on and...