Pwyll Pendefig Dyfed

This is a little known example of Schroedingers Pinnochio. His nose both grows and doesn't grow at the same time.

There was a Doctor Who sory I read once (I'm not sure if it was a TV episode or not) which had Silicon based Alien invaders.

My hangover cure is to drink water with a soluble vitamin C tablet in it, along with vitamin B complex. If I'm drinking again the next day, then a pint as soon as possible after waking works well (although it seems to be frowned upon by the medical commuity). If I'm not drinking the next day a lie in in a dark room works.

You can also use calibre to convert RTF Word documnents to mobi format.

One of the problems I've seen with people saying that they're against cencorship is that it may lead to abuse of free speech. IMO making (for example) racist comments is not acceptable, even though the racist would claim free speech.

I've just realised I forgot the word not in that first sentence Is it possible to edit post6s by the way?

Shark certainly is not a relic of a dinosaur, it's a fish! Crocodiles a reptiles, which aren't descended from dinosaurs, and a Komodo (I believe) is a lizard, again not descended from dinosaurs. With respect to geological formations, then I'd suggest that somewhere with lots of igneous rock is unlikely to have fissils as the lava would melt them! Sedimentary rocks would be more likely.

Molecules could exhibit Van der Waals forces, dipole-dipole attractions and hydrogen bonding between them. Ions would exhibit electrostatic attraction between them.

a) is a moles question. Calculate the number of moles of HCl, then using a balanced equation work out the moles of Na2CO3. Once you've got the moles, you can work out the mass. b) use your answer to part a to answer part be as a percentage.

or: the indicator is used to tell when the sodium hydroxide has been completely neutralized.

Think about the definition of an acid, then the formulae of the two acids.

It could be an osmosis experiment, where the OP needs to calculate the concentration of the potato.

At normal temperature and pressure it's going to go the other way: H2O2 -> H2O + O2 The question is whether it is an equilibrium reaction, so can uthe equilibrium be shifted the other way by changing the temperature and/or pressure (using Le Chateliers principle)

The first step (not the last step) is the slow, rate determining step.

Do you have an example of the type of question you're referring to?

Are you talking about an ionic half equation? If so the easiest way to do it would be to balance the electrons.

I don't quite understand what you're asking here. There is an electrostatic force attracting the positive ions to the negative ions. This force is similar to gravity in that the further away the ions are from each other, the smaller the attraction will become. The ions will attract those closest to each other.

Calculate the number of moles of each element.

You need to look at it terms of moles. Calculate the number of moles of Hydrogen, and the number of moles of oxygen (in 2g each). You can then use the balanced equation to calculate how many moles of water could be formed. Convert the number of moles back into mass, and you'll find your figures are true. 2.25g of water formed, and 1.75g of hydrogen left unreacted.

Ahhh, thanks. Would that bit in bold be linked to the size of the fluoride ion? Chlorine doesn't exhibit hydrogen bonding (even though it's very electronegative - more than Nitrogen IIRC which does exhibit H-bonding) but Fluorine does - kind of thing?

I recently saw a question about the difference between strong and weak acids. The question stated that hydrochloric acid is known as a strong acid as it dissociates completely, whereas a weak acid would reach a dissociated equilibrium (or words to that effect). This is true for acids such as ethanoic acid of course, the question used hydrofluoric acid as an example. I was under the impression that Hydrofluoric acid is a strong acid, and the electronegativity of fluorine would mean that it would readily form the fluoride ion. Is there a mistake in this question, or is there a reason why some could consider hydrofluoric acid a weak acid?

A far safer fireball is to light a splint, keeping it around 2cm off the floor (using a stand and clamp for example). Then sprinkle dried (fine) powdered milk onto it. The flame leaps up throught particles of dried milk, resulting in a fireball.

Sorry. Is it possible to edit the reply?

Not molarity exactly, that's to calculate the number of moles in solution. Number of moles = mass / Mr 1 mole contains 6 x 10^23 particles - Avogadros number. This is the equivalent to the number of atoms in 12 grams of the Carbon - 12 isotope.

Ah, get you, sorry, I misunderstood you I meant atomic mass numbers, but wrote it as atomic mass (as oppose to mass number)