Chemistry - May 2007

2007-05-20 05:03:53 · 1 answers · asked by Foxy 1

The pH of a solution is 9.0. what is its h3o concentration?

options are
9 M
1x10(-5) M
1 x 10(-7) M
1 x 10(-9) M

2007-05-20 04:14:54 · 6 answers · asked by Anonymous

2007-05-20 02:33:18 · 4 answers · asked by Arumugakannu N 1

2007-05-20 02:30:54 · 7 answers · asked by juno 1

What is the reason for this relation between explosives and nitrogen content ?
Are their other elements of the nitrogen group (like halogens is the group for chlorine , fluorine etc ) that share this same propensity to form highly explosive compounds ?

2007-05-20 00:58:01 · 5 answers · asked by shogunly 5

H2
NH3
H2O
HCL
CH4
C2H6

and why?

thanks

2007-05-20 00:41:21 · 1 answers · asked by Anonymous

2007-05-19 20:42:35 · 1 answers · asked by Anonymous

For these problems : Assume that the reactions are being performed at a pressure of 1.0 atm and a temperature of 298K

1) Calcium carbonate decomposes at high temperatures to form carbon dioxide and calcium oxide: CaCO3 -> CO2+ CaO
How many grams of calcium carbonate will I need to form 3.45 liters of carbon dioxide?

2) Ethylene burns in oxygen to form carbon dioxide and water vapor: C2H4 + 3O2 -> 2CO2 + 2H2O, How many liters of water can be formed if 1.25 liters of ethylene are cosumed in this reaction?

2007-05-19 20:15:05 · 2 answers · asked by Anonymous

malondialdehyde is the end product of lipid peroxidation.
Its an important markers of lipid peroxidation by free radical.

2007-05-19 20:02:00 · 3 answers · asked by Anonymous

2007-05-19 19:46:41 · 3 answers · asked by shutong218 1

i really need a flow chart for this and i can seem to have an exact answer... please help! thank you!

2007-05-19 19:44:41 · 3 answers · asked by azn_venus2004 1

why are transition metals able to display variable oxidation states?

2007-05-19 19:34:18 · 2 answers · asked by ocean_irq 1

if i originally have 100 mL of H2SO4 solution (unknown concentration)and add 400 mL water to the solution. Then take 25 mL of the diluted solution into another beaker. add NaOH with a concentration of 0.1M (0.1 mole per litre) to the 25mL solution in order to neutralise. if it takes 118 mL of NaOH to neutralise the H2SO4 solution, how can i work out the concentration of the diluted H2SO4 solution and the concentration of the original H2SO4 solution.???

2007-05-19 19:28:40 · 2 answers · asked by Labuuu* 1

chemistry model on ''future fuel" in vision 2020

2007-05-19 19:23:33 · 2 answers · asked by Anonymous

how can i find this flowchart/ flowdiagram on the internet? i've been looking around, but i just cant seem to find it! i also need the chemical formulas as well!

2007-05-19 19:18:10 · 1 answers · asked by azn_venus2004 1

2007-05-19 19:13:58 · 2 answers · asked by analiz o 1

2007-05-19 19:10:29 · 1 answers · asked by Anonymous

2007-05-19 19:05:57 · 2 answers · asked by Anonymous

Is there any catalyst to speed-up fermentation process? I understand that if we have high temperature, fermentation is fast but at room temperatures, or even at 120 +/- degree F temperatures, it is taking about a week. I wonder is there any catalyst we can use to speed-up the process?

2007-05-19 19:05:39 · 1 answers · asked by atiqmalik73 1

Consider the oxidation of ammonia NH3 by oxygen O2 to form nitrogen dioxide NO2 and water H2O :
4NH3(g) + 7O2(g) ® 4NO2(g) + 6H2O(l)

Suppose that in this reaction water is being formed at a rate of 13.6 moles liter-1 sec-1. At what rate (in moles liter-1 sec-1) is oxygen used up?

2007-05-19 18:46:04 · 3 answers · asked by Bruce 1

2007-05-19 18:39:35 · 2 answers · asked by Anonymous

Greetings, I am a grade 12 student, and I need some assitance with this question:

2NaOH + H2SO4 --> 2H2O + Na2SO4

From looking at this equation, how does the number of moles of H30 ions compare with the number of moles of sulfuric acid present? Use the results to determine the number of moles of H30 present in sulfuric acid

Given:
vH2S04: 10.0mL (.001L)
vNaOH: 11.2mL
number of moles of h30 present in NaOH = .001

Thank you for help.

2007-05-19 18:27:40 · 1 answers · asked by Anonymous

my son is going to be sophmore this august. he has almost failed in biology bcos he said biology is boring! he likes mathematics, history & art. he wanted to take chemistry but the teacher disapproves it. so he takes environmental science reluctantly but still wants to take chemistry? i used to like biology but have no idea abt chemistry. is chemistry boring?

2007-05-19 18:18:27 · 2 answers · asked by yb H 2

I know sucrose, C12H22O11, is a covalent compound..
How many valence electrons are involved in the bonding in sucrose?
How many total electrons are present in one unit of this compound?

2007-05-19 18:04:15 · 1 answers · asked by soccrrulz21 2

Sucrose, which is table sugar, breaks down slowly in aqueous solutions to form smaller sugar molecules. If a small amount of acid is added to such a solution, the reaction goes much more quickly, even though the acid is not used up in the reaction. What role is the acid playing in this reaction?

2007-05-19 18:02:32 · 1 answers · asked by soccrrulz21 2

A white powder, consisting of a simple mixture of tartaric acid (C4H6O6) and citric acid (C6H8O7) was analyzed to determine the elemental composition. Combustion of a 548.0-mg sample produced 682.3 mg of CO2 and 200.3 mg of H2O.

Use atomic masses: C 12.011; H 1.00794; O 15.9994.


Calculate the % carbon, by mass, in the sample.
Calculate the % hydrogen, by mass, in the sample.
Calculate the % oxygen, by mass, in the sample.
Calculate the % citric acid, by mass, in the sample.

2007-05-19 17:53:58 · 1 answers · asked by Anonymous

2007-05-19 16:32:04 · 2 answers · asked by HA! HA! HA! 5

In the electron configuration 1s2,2s2,2p5, how does the the sum of the angualr quantum number add up to 5?

2007-05-19 16:31:29 · 3 answers · asked by Chuck 1

What are the units of rate??

2007-05-19 16:20:58 · 4 answers · asked by Anonymous

2007-05-19 16:20:25 · 6 answers · asked by Anonymous