Chemistry - October 2007

I know that it would occur on an ortho or para position (right?), but I don't know what ring or how to tell. Please explain it too.

2007-10-15 05:51:05 · 3 answers · asked by Kiko 3

What is the Delta H_rxn for the following reaction:


CaO(s) +CO_2(g)---->CaCO_3(s)

Use the following reactions and given Delta H

Ca(s) +CO_2(g) +1/2 O_2(g)-----> CaCO_3(s)

Delta H= -812.8 KJ

2Ca(s) + O_2(g)----> 2CaO(s) Delta H= -1269.8 KJ

2007-10-15 05:51:04 · 2 answers · asked by Anonymous

coenzyme Q
NAD+
flavoprotein (FP)
cytochrome b

2007-10-15 05:47:21 · 2 answers · asked by Anonymous

They both are straight chain compounds.
Both of these compound classes have as the smallest compound a 5 carbon skeleton.
Aldehydes and ketones both contain a carbonyl carbon.
Aldehydes and ketones have no shared characteristics.

2007-10-15 05:45:14 · 2 answers · asked by Anonymous

Can someone explain what rust is exactly please? Is it just the metal reacting with oxygen?

If so, how is this different from the oxides formed when a metal is heated and combined with oxygen?

Why can you reverse one and not the other?

2007-10-15 05:43:41 · 5 answers · asked by db 3

How many grams of will be needed to produce 575mL of a solution that has a concentration of Na^+ions of 1.40 M?


mass of Na3PO4 =________
I have tried & still don't get the correct answer.

2007-10-15 05:42:27 · 5 answers · asked by cvkl 1

a primary alcohol
a secondary alcohol
a tertiary alcohol
an acetal

2007-10-15 05:39:44 · 4 answers · asked by Anonymous

What websites are there to revise AS Chemistry (Nuffield/Edexcel) where it just lets me know in brief what exactly I need to know rather than sifting through the thick textbook and not knowing. I have tried 'chemguide' but not found this useful in terms of stating what is in each chapter clearly.

2007-10-15 05:38:12 · 4 answers · asked by Anonymous

2007-10-15 05:37:27 · 4 answers · asked by jason k 1

glucagon
insulin
epinephrine
more than one response is correct

2007-10-15 05:36:34 · 4 answers · asked by Anonymous

Given the following data:
PCl5(s) → PCl3(l) + Cl2(g) ΔH = +123.8 kJ
4PCl3(l) → P4(s) + 6Cl2(s) ΔH = +1278.8 kJ

Find the ΔH of the following reaction:
P4(s) + 10Cl2(g) → 4PCl5(s)

2007-10-15 05:36:28 · 2 answers · asked by Anonymous

Enzymes can either speed up or slow down a chemical reaction.
Enzymes are not used up during the chemical reaction in which they are involved.
Enzymes are proteins that are capable of reducing the activation energy.
There are enzymes that interact with one enantiomer, but not the other.

2007-10-15 05:35:49 · 2 answers · asked by Anonymous

Given the following data:
TiBr2(s) + SnCl4(l) → SnBr2(s) + TiCl4(l) ΔH = -74 kJ
SnCl2(s) + Cl2(g) → SnCl4(l) ΔH = -195 kJ
SnBr2(s) + TiCl2(s) → SnCl2(s) + TiBr2(s) ΔH = -4.2 kJ

Find the ΔH of the following reaction:
TiCl2(s) + Cl2(g) → TiCl4(l)

2007-10-15 05:34:29 · 3 answers · asked by Anonymous

I'd like to hear from peole with a bachelor's or master's degree in chemistry: how do you find the job market? How easily did you land a job in your field? If you have a job in your field, how good is it? Do you feel it was worth getting the degree?

2007-10-15 05:32:54 · 2 answers · asked by winback 1

2007-10-15 05:32:39 · 4 answers · asked by Shreemathi T 1

2,2-Dimethyl-1- bromopropane and bromoethane, both primary alkyl halides undergo SN2. Which one of them would react slower in the reaction and why?

I know that the stronger the nucleophile, the faster the rate of the SN2 reaction, but could someone please explain how to find if one is stronger than another? I know that bromoethane has a simpler structure, but that have anything to do with this question?

Thanks for any help. :-)

2007-10-15 05:32:24 · 2 answers · asked by John D 3

A 525 g piece of copper tubing is heated to 92.8°C and placed in an insulated vessel containing 47.5 g of water at 39.0°C. Assuming no loss of water and heat capacity for the vessel of 10.0 J/K, what is the final temperature of the system (c of copper = 0.387 J/g·K)?

2007-10-15 05:25:16 · 2 answers · asked by divastr186 2

i am student of 12th standered so tell acc to it.
i shall be thankfull to u

2007-10-15 05:21:42 · 4 answers · asked by angel 1

CH2CH3 was axial and H is equatorial, if they were swapped around, would they be constitutional isomers?

The 2 other options are..diff combinations of the same compounds or stereoisomers that cannot be interconverted by rotation around single bonds?

2007-10-15 05:15:35 · 2 answers · asked by Anonymous

a.. describe the flame obtained from a bunsen burner with the hole open, and compare it to the flame obtained with the air hole closed

b..explain why the two flames are so different (hint:think about how oxygen gets mixed with the fuel)

2007-10-15 05:14:16 · 4 answers · asked by Babiiee Laura Jaynee =] 1

I need to find 3 bases that are capable of removing the most acidic hydrogen from methanol (CH3OH), ethylene (C2H2), and methylamine (CH3NH2). My problem is that I don't have a good pKa table and to use the one in my book you need to know what exactly what you are looking for. Also, how do you know the pKa of the base and conjugate base since the pKa value only pertains to acids? I think I might be making it harder than it is but I'm really confused.

2007-10-15 05:14:02 · 3 answers · asked by LaLa 1

There were several reactions that I made all involving the use of HCl. For example, NaNO2 + HCl, NaNO3 + HCl, and FeS + HCl. What product forms from these types of reactions involving this strong acid, HCl? How do I know when H2O or CO2 forms due to the use of acid?

I understand that an acid and a base gives a neutralization reaction, which leaves behind a salt. I'm not quite sure what happens with all others. Please don't just give me an answer, but, I need a concise explanation as well.

2007-10-15 05:13:35 · 3 answers · asked by Anonymous

what is the molarity of a .1% auxin (IAA) solution. It also said noted that .1%=1g/L. THe formula weight of IAA is 186. So what is the molarity? I got an answer, and I just want to make sure it is correct! Thanks

2007-10-15 04:56:57 · 1 answers · asked by pacificglo1 2

what is the concentration of blood. level of water in urine and concentration of urine in the hot eating salt and when you drink lots of liquid? :\

2007-10-15 04:52:00 · 1 answers · asked by Anonymous

I cant remember how to do molarity questions. basically we have IAA, whose formula weight is 186, and we need to find how many grams of it would take to prepare 500mL of a .5M solution. Thanks!

2007-10-15 04:46:04 · 4 answers · asked by pacificglo1 2

2007-10-15 04:33:08 · 0 answers · asked by Lindsey G 1

I have an old glass thermometer that is close to getting broke and its the type that uses mercury. Where can i go to dispose of it? Also what can i do to dispose of it safely?

2007-10-15 04:13:47 · 3 answers · asked by porschegt 2

2007-10-15 04:05:16 · 12 answers · asked by Dylan B 1

Because all matter is composed of atoms, the number of neutrons and protons in each atom must be equal.

TRUE or FALSE


I think TRUE for the second part but the first part with the "Because all matter is composed of atoms..." is confusing me!!! Is that WHY they are equal??? I hate these type of questions!!

2007-10-15 04:04:40 · 5 answers · asked by LJC 2

My son has homework regarding the above. He has to find out the type of decay for Radium, Radon, Actinium, and chenical symbol Th.
Anyone have a clue about this.

2007-10-15 04:03:58 · 3 answers · asked by Anonymous