Chemistry - February 2007

When a substrate that is catalyzed by an enzyme is present in high concentrations, the effect on the rate of a reaction by changeing the substrate concentration can be described using zeroth-order kinetics. If the concentration of a such a substrate is changed from 2.25 × 10−3 M to 4.12 × 10−1 M, by what factor does the rate of the reaction change ?



That is rate (4.12e-1M) = f × rate (2.25e-3M)

what is the vaule of f ?

2007-02-08 02:22:32 · 2 answers · asked by manutd11191988 1

When enzymes are present in very low concentrations, their effect on the rate of a reaction can be described using first-order kinetics. If the concentration of a catalyzing enzyme is changed from 3.46 × 10−3 M to 5.68 × 10−1 M, by what factor does the rate of the reaction change ?

2007-02-08 02:20:46 · 2 answers · asked by manutd11191988 1

2007-02-08 02:15:17 · 4 answers · asked by Anonymous

2007-02-08 02:13:11 · 2 answers · asked by Anonymous

I was told to make a 2/25 dilution of a solution with water. If I had 30 mL the solution....how much water should I add? I just don't understand what the ratio implys.

2007-02-08 02:12:51 · 6 answers · asked by Anonymous

2007-02-08 02:05:37 · 6 answers · asked by goring 6

tell me all about this(the gas released,reactions of this gas with heamoglobin).how this initiated

2007-02-08 02:01:45 · 10 answers · asked by vk 1

2007-02-08 01:27:30 · 1 answers · asked by dominique r 1

I am looking and my chemistry..and i cant seem to find the answer for this answer

2007-02-08 01:16:19 · 2 answers · asked by Anonymous

Im working on a science fair project. I'm using a syringe and connecting it with another syringe. between the syringes are tubes to connect them. Im putting air and water into it. I'm trying to figure out what is easier to push air or water?? please help me! i need to know what happens to water when u compress it. What happens to its molecules??

2007-02-08 01:10:58 · 5 answers · asked by Kate L 1

2007-02-08 01:02:29 · 5 answers · asked by oleander 3

I am in 11th standard. I have to make a project on one of these topics. Topics are :
1. metallurgy
2. chemistry of non - metals
3. chemistry of havier metals [ zinc, lead, tin ]
4. states of matter
5. structure of atom
6. hybridization
Plz, send me some matter & diagrams on any of these topics.

2007-02-08 00:57:48 · 4 answers · asked by Bhavitavya P 1

I saw it once, and i forgot what the name of it was.

2007-02-08 00:54:16 · 4 answers · asked by Miss LaStrange 5

2007-02-08 00:40:20 · 2 answers · asked by leyna_nguyen_0702 2

2007-02-08 00:36:13 · 12 answers · asked by Neil C 1

And if so, what is in lower carat gold apart from gold?

2007-02-08 00:31:52 · 11 answers · asked by Alyosha 4

2007-02-08 00:29:08 · 8 answers · asked by Sierra 1

I need a reasonably reliable, literature value for the energy of dissociation of a lithium carbon bond, to form Li+ and a carbanion, and I cannot find one. Does anyone have such a value that I can reference?

2007-02-08 00:23:32 · 1 answers · asked by Ian I 4

i am doing a botany experiment involving silver thiosulphate solution. i have made the solution as per advised with 2.5 grams of silver nitrate. made up separately and 5 grams of sodiumthiosulphate. made separately. both were disolved into 2 x 500 mills of distilled water. once disolved they were mixed together while stirring briskly. when the solution had cleared there was a fair amount of black sediment suspended in the bottom of the solution. is this normal and has it mixed correctly or have i erred with something. the solution is supposed to stain skin brown.permanently. it does not do so..as you can see, i'm no chemist. just an keen amateur botanist. one last point, both the ingredients were both pure as . thank you.

2007-02-08 00:00:39 · 1 answers · asked by JAMES M 1

My question is simple, yet a thorough search of Google brought me no closer to finding the answer. I found countless articles explaining what the emission spectra of an element was, but none which satisfactorily told me why they contained more than one line.

I understand the core concept. That is, if you add energy to an atom, which may be the heat from the Bunsen flame, the atoms will gain that energy and their electrons may be promoted to a higher energy level. Since this energy level is unstable the excited electrons return to their stable state, emitting energy as visible light, the frequency of which directly relates to difference between energy levels.

My question is do all the electrons jump when energy is applied to them? Do only a selected few jump? Are the jumps for a particular element consistent? What precisely produces the unique spectra for each element? Why, my brain moans to find the answer!

Smart answers please, I also thank you in advance.

2007-02-07 23:39:49 · 2 answers · asked by iamdaroot 2

Someone stated to me that spearmint is used to relieve heart burn. I was wonder if this is because it's an acid or a base?

2007-02-07 23:24:06 · 1 answers · asked by PantsStatusZero 2

job description of laboratory equipment application specialist

2007-02-07 23:09:30 · 1 answers · asked by osuman m 1

2007-02-07 22:12:40 · 4 answers · asked by bhoo 1

What is the volume in Liters of a 7.85x10(to the 4th power) g sample of copper if the density of copper is 8.90g/mL?

One penny weighs 2.50 grams and has a density of 6.94g/mL. If you drop 50 oennies into a beaker with 250.0 mL of water in it, what will be the total volume in the beaker? What will be the total mass in the beaker?


I have no idea how to do these two problems. Any help would be wonderful!

2007-02-07 21:51:09 · 2 answers · asked by ... 2

I need to find out, for my course work, ' the industrial preparation of ammonium sulphate'. I have look on loads of sites but can't find the right thing, please help. I think I need to write about 2 paragraphs.
Thanks

2007-02-07 21:26:32 · 3 answers · asked by ATB 2

This is a question I am having probelms with. The answers to choose from are:

a. 5f
b. 3p
c. 2s
d. 4d

I thought that both the "p" and the "d" form a spherical charge cloud, but you can only choose one answer.

Could someone please explain to me which one is right and why.

I am thinking the 4d answer but it just doesnt make any sense.

Thank You!

2007-02-07 21:18:53 · 5 answers · asked by Silence06 2

2007-02-07 20:45:54 · 1 answers · asked by vinny 1

2007-02-07 19:27:54 · 2 answers · asked by Anonymous

Calculate the % acetone,% ethyl alcohol, and water in the solution?

2007-02-07 19:03:43 · 2 answers · asked by ishika65 1

2007-02-07 18:32:10 · 15 answers · asked by ishika65 1