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How long is the cell cycle of a human brain cell, a human liver cell and a yeast cell? Thanks very much!-- 208.65.244.21
Hi. I was wondering if someone could give me a list of all the future weapon that are currently been researched(doesn't have to be complete). Not new model, but new things that you might expect in a science-fiction movie like raygun or forcefield. Thanks
I was trying to find out what the proportions are of iron ore,coke,and limestone were needed to produce a tonne of iron. Then what was needed to make this into steel .
Use the blast furnace formula, then include the Molar masses of the substances, then factor down to 1 t of product. It's not really a chemistry question, rather one of Maths. Englishnerd 14:12, 29 October 2006 (UTC)
A special satalite was lanched to make a Cosmic Ray map of the universe. Havw any othe maps of the universe been made based on the spectrum and presence of the elements? Adaptron 15:47, 29 October 2006 (UTC)
I would like to find out the energy density per gram and kilogram of wood,petrol,natural gas,butter and coal.justin chung 29/10/06
What does the chemical structure of sodium phosphate look like and what is the melting point, boiling point of sodium phosphate? —The preceding unsigned comment was added by 65.6.192.7 ( talk • contribs) .
not forgetting of course, disodium hydrogen phosphate Na2HPO4 and sodium dihydrogen phosphate NaH2PO4. just to complicate matters. Xcomradex 20:35, 29 October 2006 (UTC)
You can call it sodium phosphate. It's a perfectly acceptable nomenclature. Phosphate always have -3 charge, and sodium always has +1 charge when it's in a salt with a anion, so you can work out (yea, it's pretty tricky) that it's trisodium. Aaadddaaammm 23:57, 29 October 2006 (UTC)
Of the known genetic sex-determination systems (e.g. XY, ZW etc.), which were the first to exist in chordates? -- Burbster 20:09, 29 October 2006 (UTC)
Hi! Could somebody tell me what are the best studies to do in order to study the computational side of the brain, i.e. the bridge between the neuron scale and the brain superior functions scale? Thanks, David
Hi there did ask this question before, but do not know if anyone replied as I have forgotten where I put the question. Am now registered so here I go again.
I am studying a Single Hons Degree in Psychology and am having great difficulty with independent variables, dependent variables etc.
Is there someone who could possible help me in as plain a way as possible - idiot friendly, am 49 and have no idea what I am doing or not doing.
-- Caroledom57 23:12, 29 October 2006 (UTC)
Ok, fine, I'll admit, it's hw. I don't really care about the answer as much as the methodology behind solving it.
I'm supposed to write a balanced equation for the acid base equilibrium for potassium azide dissolved in water, and calculate the equilibrium constant for it, and calculate the pH of a .1M solution in water.
I have the acidity constant for a hydrazoic acid (HN3). is that used to write the balanced equation? The conjugate base is N3- is that used to figure out that the equation is going to be something like KN3 + H2O --> HN3 + KO2
does that make sense? and would the equilibrium point be the pKA value for this?
also, how would I calculate the pH of a .1M solution? Just figure out the [H+] concentration at that molarity? That's what I'm thinking.
Anyways, any help along the way would be appreciated, because I'm really confused. Thank you guys so much!
I've already looked at several articles on here, including the pKa and acid equilibrium article. Thanks for your help! 130.207.180.80 23:26, 29 October 2006 (UTC)
would the potassium act in the same way as sodium? sodium azide is much more common, and they're in the same group. just a follow-up question. thanks!
130.207.180.80
23:32, 29 October 2006 (UTC)
The reaction will be: HN3 + H2O <--> N3- + H3O+
OR
HN3 <--> N3- + H+
The Ka value is
You then assume concentration of H3O+ = concentration of N3-, and that the concentration of HN3 is unchanged because only a little bit of it dissociates to N3- + H3O+.
This gives
You then plug in Ka and the concentration of HN3 and solve for H3O+.
Then plug your concentration of H3O+ into the equation et voila!
Don't worry about the K/Na at all. They're just counter ions and should have no effect on the pH. Hope that helps and that I didn't make any big mistakes in there. Have a look at [2] too. Aaadddaaammm 23:51, 29 October 2006 (UTC)
Science desk | ||
---|---|---|
< October 28 | << Sep | October | Nov >> | October 30 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
How long is the cell cycle of a human brain cell, a human liver cell and a yeast cell? Thanks very much!-- 208.65.244.21
Hi. I was wondering if someone could give me a list of all the future weapon that are currently been researched(doesn't have to be complete). Not new model, but new things that you might expect in a science-fiction movie like raygun or forcefield. Thanks
I was trying to find out what the proportions are of iron ore,coke,and limestone were needed to produce a tonne of iron. Then what was needed to make this into steel .
Use the blast furnace formula, then include the Molar masses of the substances, then factor down to 1 t of product. It's not really a chemistry question, rather one of Maths. Englishnerd 14:12, 29 October 2006 (UTC)
A special satalite was lanched to make a Cosmic Ray map of the universe. Havw any othe maps of the universe been made based on the spectrum and presence of the elements? Adaptron 15:47, 29 October 2006 (UTC)
I would like to find out the energy density per gram and kilogram of wood,petrol,natural gas,butter and coal.justin chung 29/10/06
What does the chemical structure of sodium phosphate look like and what is the melting point, boiling point of sodium phosphate? —The preceding unsigned comment was added by 65.6.192.7 ( talk • contribs) .
not forgetting of course, disodium hydrogen phosphate Na2HPO4 and sodium dihydrogen phosphate NaH2PO4. just to complicate matters. Xcomradex 20:35, 29 October 2006 (UTC)
You can call it sodium phosphate. It's a perfectly acceptable nomenclature. Phosphate always have -3 charge, and sodium always has +1 charge when it's in a salt with a anion, so you can work out (yea, it's pretty tricky) that it's trisodium. Aaadddaaammm 23:57, 29 October 2006 (UTC)
Of the known genetic sex-determination systems (e.g. XY, ZW etc.), which were the first to exist in chordates? -- Burbster 20:09, 29 October 2006 (UTC)
Hi! Could somebody tell me what are the best studies to do in order to study the computational side of the brain, i.e. the bridge between the neuron scale and the brain superior functions scale? Thanks, David
Hi there did ask this question before, but do not know if anyone replied as I have forgotten where I put the question. Am now registered so here I go again.
I am studying a Single Hons Degree in Psychology and am having great difficulty with independent variables, dependent variables etc.
Is there someone who could possible help me in as plain a way as possible - idiot friendly, am 49 and have no idea what I am doing or not doing.
-- Caroledom57 23:12, 29 October 2006 (UTC)
Ok, fine, I'll admit, it's hw. I don't really care about the answer as much as the methodology behind solving it.
I'm supposed to write a balanced equation for the acid base equilibrium for potassium azide dissolved in water, and calculate the equilibrium constant for it, and calculate the pH of a .1M solution in water.
I have the acidity constant for a hydrazoic acid (HN3). is that used to write the balanced equation? The conjugate base is N3- is that used to figure out that the equation is going to be something like KN3 + H2O --> HN3 + KO2
does that make sense? and would the equilibrium point be the pKA value for this?
also, how would I calculate the pH of a .1M solution? Just figure out the [H+] concentration at that molarity? That's what I'm thinking.
Anyways, any help along the way would be appreciated, because I'm really confused. Thank you guys so much!
I've already looked at several articles on here, including the pKa and acid equilibrium article. Thanks for your help! 130.207.180.80 23:26, 29 October 2006 (UTC)
would the potassium act in the same way as sodium? sodium azide is much more common, and they're in the same group. just a follow-up question. thanks!
130.207.180.80
23:32, 29 October 2006 (UTC)
The reaction will be: HN3 + H2O <--> N3- + H3O+
OR
HN3 <--> N3- + H+
The Ka value is
You then assume concentration of H3O+ = concentration of N3-, and that the concentration of HN3 is unchanged because only a little bit of it dissociates to N3- + H3O+.
This gives
You then plug in Ka and the concentration of HN3 and solve for H3O+.
Then plug your concentration of H3O+ into the equation et voila!
Don't worry about the K/Na at all. They're just counter ions and should have no effect on the pH. Hope that helps and that I didn't make any big mistakes in there. Have a look at [2] too. Aaadddaaammm 23:51, 29 October 2006 (UTC)