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kumorifox
I'm a postdoctorate researcher in analytical chemistry. I've always loved science, particularly chemistry, and I'll help when I can. I enjoy answering questions and helping others, that's the main reason I'm here.
How was this answer derived?
I once read a riddle in a magazine that deals with probability. The answer was given in a different issue, but I never found out why that was the answer. Could someone help me there?
The minister for transport wants as many students to get week passes as weekend passes for public transport. He takes a large pile of envelopes and puts week passes in half of them, and weekend passes in the other. When they are on the belt to send them off, the Prime Minister sees the envelope for his son pass by and quickly adds a weekend pass. After a bit, a councillor spots an envelope with two passes. He takes one out: a weekend pass.
What is the probability that the son of the Prime Minister is stuck with a weekend pass?
The answer was given as 2/3. I have no clue how this was obtained. Can someone enlighten me?
2 個解答Mathematics1 十年前Question for atheists, out of curiosity?
I got to thinking yesterday, what images do atheists get if they were to imagine Heaven or Hell? Religion has ideas on what Heaven and Hell are like (such as torture, fire and brimstone for Hell). But if you hear the words Heaven or Hell, aside from the thought that they don't exist, what images form (if any)? Or are there earthly situations you'd describe as being in heaven or being in hell?
I have my own ideas about what they would be like, but I'm just curious to know what others think.
I'm agnostic, BTW. Just throwing that in there.
14 個解答Religion & Spirituality1 十年前Are daughter atoms from radioactive decays ions?
When a radioactive atom decays, particles are emitted. In the case of electron capture and positron decay, charges will remain balanced. However, in the case of alpha and beta decay, excess positive or negative particles are emitted. Will this have an effect on the charge of the daughter atom?
For example, Tc-99 decays by emitting a beta particle. Its nucleus will gain an extra proton, but the electron formed is ejected, and doesn't become part of the atom. Will the resulting Ru-99 atom be Ru+?
3 個解答Chemistry1 十年前DNA, RNA, codons and amino acids?
I'm unsure exactly how the genetic code works. I know that each of the 20 amino acids has between 1 and 6 codons coding for them. However, I don't know on which part the order is found.
For example, methionine is carried on the AUG codon. Is this sequence found on the three-nucleotide transfer RNA that is bound to the methionine residue, or is it a section on the messenger RNA that acts as the link between the DNA and the ribosome?
And what exactly is meant with 5'-3' sequencing, or however it is actually stated? How do you know which part is the 5'?
I'm not a biochemist, but I am curious as to how this works. I've been unable to find it anywhere so far. Thank you for taking the time.
2 個解答Biology1 十年前Smileys in Yahoo! Messenger?
I recently updated my Yahoo! Messenger to the latest version. However, all the smileys have changed. I used to have large and fairly defined ones, but they have been replaced by smaller ones.
The "rolling on the floor" smiley, for example, would be rolling over on its side, then onto its back, but then it would roll over completely and pound the floor. The one I have now just rolls from its back to its side and back again.
Does anyone know how I can get the old ones back? I thought they were way nicer ones.
2 個解答Other - Yahoo Messenger1 十年前Would you do something like this?
A friend of mine told me that his best friend broke off their friendship after my friend came out to them as being homosexual.
Would you do something like that to a life-long friend? If a friend trusted you so much that they reveal something about themselves, something they think you deserve to know?
Don't give me stuff like "Homosexuality is against the Bible" or things like that; those answers will not remotely be considered and, to me, make you out as someone without the ability to have a personal opinion. I'm asking for a personal opinion, not one people feel you are expected to say.
I'm just curious as to the reasons people would do such a thing.
13 個解答Other - Society & Culture1 十年前Why are copper(II) salts sometimes more stable than copper(I)?
When you look at the electron configuration of neutral copper, it is 1s2 2s2 2p6 3s2 3p6 4s1 3d10. Assuming that the two most stable electronic states for an atom or ion mean a full outer shell or a half-full outer shell, neutral copper should be quite stable (1 half full and 1 full). Copper(I) should have the configuration ... 4s0 3d10, a full outer orbital. Copper(II) would have ...4s0 3d9, neither full nor half-full. How come it has quite a high stability, as in, for example, copper(II) sulphate, seeing that copper(I) sulphate does not exist?
4 個解答Chemistry1 十年前When an ice cube is added to a fizzy drink, why does it bubble?
Whenever an ice cube is added to a fizzy drink, it starts to froth and bubble. This means that the carbon dioxide is expelled from the solution. But if I remember correctly, gas solubility in a liquid should increase with decreasing temperature. Why, then, is the gas expelled from the solution?
2 個解答Physics1 十年前