0
votes
0answers
4 views

Proof of dissociation constant Kd of a binding reaction is half the saturation point ONLY if protein (or macromolecule) =< Kd

We know Kd = [P][L]/[PL] ---(0) for the equilibrium P + L <=> PL where P is a protein and L is a ligand. Let [P]t be total protein concentration and [L]t be total ligand concentration. Hence, Kd ...
0
votes
0answers
6 views

How does Temperature influences the rate of protein turnover?

A very similar question I asked can be found here. It seems that this other question as I formulated it has a hard time attracting answer, so I'm giving another try with a slightly different question. ...
1
vote
0answers
5 views

Salt concentration and electrical permittivity of water

We know that the electric flux density $D$ can be related to electric field intensity $E$ as $D=\epsilon(\omega) E$ $\epsilon(\omega) = \epsilon_0 \epsilon_r(\omega) $ where $\epsilon_0$ is the ...
0
votes
2answers
24 views

How to interpret the MSDS warning?

Just a quick question; I was looking up the MSDS for o-Toluic Acid for an experiment when I came across this in the "Hazards Identification" section. ...
2
votes
1answer
27 views

Why is it sugar what is used in low-cost homemade rockets?

I was thinking about making a "rocket candy". It's relatively inexpensive rocket based on sugar and some oxidiser, mostly $\ce{KNO3}$. The fuel us usually formed by heating the mix of both compounds ...
8
votes
2answers
206 views

Carbon atoms at the edge of diamond

It is well known (the simplest exaample of textbooks) that diamond has a well-defined arrangement of sp3 carbon atoms, as each carbon is connected to four neighbor ...
0
votes
0answers
7 views

Why does brown iron oxide improve burn rate of rocket candy?

On wikipedia, this statement exists about rocket propellant aditives: Metal oxides have been found to increase the burn rate of sugar propellants. [...] Most often used are iron oxides. Red iron ...
1
vote
1answer
11 views

Simple experiments involving enantiomer synthesis

I want to do an experiment to investigate factors affecting the synthesis of chiral molecules. The only problem is, my institution doesn't have much money, and it seems like the chemicals required for ...
0
votes
0answers
10 views

The space shuttle burns liquid hydrogen and oxygen in the main engine [on hold]

If 102000 kg of liquid hydrogen is carried on particular launch. What mass of liquid oxygen is necessary for all the hydrogen burnt. $$\ce{2H2(g) + O2(g) -> 2H2O}$$
0
votes
1answer
30 views

Uncertainty / Accuracy Confusion

My simple question is: When we are given that the speed is measured within accuracy of let's say 2 percent; When the speed of something is 45, then why do we take uncertainty as 2 percent of 45 and ...
0
votes
0answers
8 views

How do you calculate the proportion of ammonia produced from different pressures in the Haber process using the equilibrium equation?

I tried to write a increase in pressure to twice as much like this: $$\frac{2(x+1)^2}{(0.5-0.5x)2(1.5-1.5x)^3}=K$$
1
vote
1answer
18 views

Approach to model solvent in a lattice: e.g. H2O in NaCl

If a lattice contains a solvent, lets say NaCl and water of crystallisation, what is the condition for a solvent molecule to change it's location? From my current point of view I assume that such a ...
0
votes
0answers
16 views

Algorithm that calculates damage from adrafinil?

is there such a thing that calculated damage of adrafinil based on dosage? lets say i take a dosage of 100mg/ day for 100 days, what would the affect be? how much % of my liver will be damaged? Do ...
0
votes
0answers
17 views

When magnesium metal is added to hydrochloric acid the following reaction takes place:

When magnesium metal is added to hydrochloric acid the following reaction takes place: $\ce{Mg(s) + 2HCl(aq) -> MgCl2(aq) + H2(g)}$. What volume of hydrochloric acid of concentration 0.10 mol dm-3 ...
0
votes
0answers
18 views

Here are four observations of the reactions of four metals

Here are four observations of the reactions of four metals. Metal F and G react slowly with water Metal H displaces metal G from its chloride salt solution Metal E does not react with dilute acids ...
0
votes
0answers
8 views

Which of the following is the most suitable reagent to test for the presence of the iodide ion in an aqueous solution?

Which of the following is the most suitable reagent to test for the presence of the iodide ion in an aqueous solution? Acidified barium chloride solution Acidified silver nitrate solution Aqueous ...
0
votes
1answer
24 views

Which of the following does not represent a possible reaction?

Which of the following does not represent a possible reaction? A.Chlorine + sodium iodide → potassium chloride and iodine B.fluorine + sodium chloride → potassium fluoride and chlorine C.bromine + ...
0
votes
0answers
7 views

Which of the following methods could be used to remove yeast from fermented sugar solution?

Which of the following methods could be used to remove yeast from fermented sugar solution? centrifuge; crystallisation; Fractional distillation; chromatography; Filtration I'm not sure wich one ...
-1
votes
0answers
20 views

percent composition of compounds [on hold]

without doing detailed calculation , estimate whether the percent composition by mass of $\ce{Sr}$ is greater than or smaller than that of $\ce{O}$ is strontium nitrate $\ce{Sr(NO3)2}$
0
votes
1answer
25 views

How could the pH of this solution rise instead of fall when exposed to the atmosphere?

I have a couple of big barrels with a 50L demi-water solution of the following nutrients: $$ \begin{array}{rl} 200~\mathrm{\mu M} & \ce{NH4NO3} & +\\ 30~\mathrm{\mu M} & \ce{KCl} & ...
0
votes
1answer
14 views

Does the iodoform reaction form hydrogen iodide or water?

I am currently learning about the iodoform reaction, i.e. when CH3COR compounds react with iodine and sodium hydroxide to form iodoform. My course book and Chemguide both says that the reaction is as ...
1
vote
1answer
61 views

Proton affinities in machine readable format?

Short: How to get proton affinities for a large list of chemicals? A database? A programming API? Longer: I have ca. 2000 chemicals (downloaded from MCM, mostly organics that occur in the atmosphere ...
0
votes
1answer
24 views

atomic mass chemistry chang

there are two stable isotopes of iridium Ir (190.96) and Ir (192.96) if you randomly pick an iridium atom from a large collection of iridium atoms which isotope are you more likely to select ??
1
vote
1answer
17 views

ATP break down and energy release?

I have a very basic question. Energy is absorbed to break bonds. Bond-breaking is an endothermic process. Energy is released when new bonds form. Bond-making is an exothermic process. But ATP breaks ...
1
vote
0answers
14 views

What kind of salts may I add in my GPC Eluent?

What kind of salts may I add in my GPC Eluent?
4
votes
2answers
948 views

Heisenberg uncertainty principle

What is the significance of the quantity 4π in the Heisenberg uncertainty principle? $Δp \times Δx = \frac{h}{4π}$
4
votes
2answers
163 views

What is Chevron with Techron fuel?

I've heard the commercials for this stuff for years, but what exactly does it do? Does it do what the commercials say it does (clean out deposits in your tank)? How well? In other words, is this ...
7
votes
1answer
301 views

What is the IUPAC systematic name for methane?

The 1993 IUPAC Blue Book claims that "methane" is a semisystematic name: Semisystematic names also exist, such as "methane", "propanol", and "benzoic acid", which are so familiar that few chemists ...
4
votes
2answers
109 views

Dibromomethane bond angles

With regard to the above professor's claim, I disagree. Bent's rule, which states that atomic p-character is concentrated in orbitals directed toward more electronegative substituents, implies that ...
4
votes
0answers
15 views

Is there a catalyst that will reduce an alcohol to an alkane?

There are many reduction methods of going from an alcohol to an alkane: http://www.transtutors.com/chemistry-homework-help/hydrocarbons/reduction-of-alcohols.aspx And there are catalytic methods of ...
1
vote
1answer
13 views

Detecting the concentration of chlorpromazine

Is there a way to detect the concentration of chlorpromazine in a small sample ; ex: human saliva, using electro-chemical analysis? Does the sensor necessarily have to be a bulky piece of lab ...
2
votes
2answers
53 views

Carboxylate “cage” concept

My professor emphasizes the concept of the carboxylate "cage" or the idea that electrons participate in resonance within a carboxylate group such as in the benzoate anion but the electrons in the ...
1
vote
1answer
25 views

Carbonyl carbon electropositivity?

Is the carbon in a carbonyl functional group electropositive? I had a professor tell me so, but I immediately refuted him, because he defined electronegativity earlier as the ability to stabilize ...
3
votes
1answer
34 views

Electrolysis of Beer

Electrolysis of water, means that the water is separated into hydrogen and oxygen. As beer also includes water, I initially thought electrolysis of beer would cause the water to separate, and the ...
3
votes
1answer
33 views

Validity of ionic resonance structures

What's wrong with ionic resonance structures? I asked one professor about them once and all he commented was "I've seen them too, and I think they're wrong." Another professor rejected an ionic ...
1
vote
1answer
28 views

Free rotation of sigma bonds; diastereomer formation; thermodynamic and kinetic products

For the reaction of 1,3-butadiene with DBr (D = heavy hydrogen), I found that several possible products could be formed. Kinetic products A pair of enantiomers is formed. One of the pi bonds ...
5
votes
1answer
180 views

What are chiral environments?

I keep seeing the term cropping up, but cannot seem to find a definition for it. My understanding is that it is an environment in which, when the isomers interact with the environment, the two ...
2
votes
1answer
20 views

Quick way to find magnetic nature of compounds or ions

According to the Molecular Orbital Theory, the method to check whether a given compound is paramagnetic or diamagnetic is to draw the molecular orbitals and then to see whether we have all the ...
0
votes
1answer
34 views

How would one express pemoline in terms of phenethylamine?

Pemoline is a psychostimulant that is no longer used in most countries. Similarly to the psychostimulants amfetamine and methylphenidate I can clearly see a phenethylamine backbone to this compound. I ...
0
votes
1answer
25 views

Determination of chlorine in swimming pool water

How do I get started? What kind of experiment do I need to carry out? What equipment would I need for this experiment? Any other help/advice is appreciated.
0
votes
1answer
15 views

Calculating collision diameter with viscosity, but not having the mass given

I've got a homework question i'm stumped on. The viscosity of the ethylene gas was measured at $99.8*10^{-7} \textrm{ N s m}^{-2}$ at $288 \textrm {K}$. Calculate the collision diameter in ...
5
votes
3answers
959 views

Which chemical is responsible for making marker ink permanent?

As asked in the question and also, a bonus question: which property of a chemical would make it 'permanent' in terms of markers?
1
vote
2answers
35 views

Does Carbon dioxide smells “cold” [on hold]

It may be a strange question. But, whenever I smell my roasted coffee,the air in the alloy smells "colder" than the air in the kitchen. Is it due to $\ce{CO2}$ degassing in the first days after ...
5
votes
2answers
95 views

Dipole moment of cis-2-butene

I need someone to back me up on this before I go confront my teacher: I was doing some analysis of the dipole moment of cis-2-butene. Let's say that the alkyl groups are both on top. Would the dipole ...
3
votes
1answer
141 views

Difference between polyethene and polyethane

The monomer in polyethene seems to drop the C=C bond and end up with a C-C bond. The polymer chain then looks like [CH2-CH2]n. If I were to look at that polymer chain I would probably call it ...
0
votes
1answer
23 views

estimating magnitude of percent and absolute error

Can someone at least give me a hint to push me in the right direction of how to estimate magnitude of the absolute and percent errors when using a smaller amount in mL of a substance for a lab ...
0
votes
0answers
22 views

How do I figure out where velocity declines?

I am stumped on one question on my biochem practice problems. We went over all of them today but my whole group was unable to figure out how to properly set up the equations to calculate the change in ...
0
votes
0answers
16 views

How do I go about finding the ratio of Ag to CO3? [on hold]

How do I go about finding the ratio of Ag to CO3 and also the empirical formula?
0
votes
1answer
29 views

Sodium metal reduction of chloroform

In discussing how best to deuterate chloroform, it occurred to me that we could use sodium metal to reduce hydrogen into hydrogen gas. If this could actually happen, this would be a great thing - we ...
0
votes
1answer
21 views

water vapor vs air (in a balloon)

I poured some water in a balloon, inflated, and tied it up. Over a period of couple weeks, all water in the balloon is gone. But the balloon is still at about 2/3 of original inflated size. I ...

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