Chemistry - July 2007

2007-07-21 05:00:04 · 2 answers · asked by summerrain 2

One of the reactions that occurs in a blast furnace (where iron core is converted into cast iron) is that iron (III) is treated with carbon monoxide to produce elemental iron and carbon dioxide. Suppose that 1.64 x 10^3 kg of iron are obtained from a 2.62 x 10^3 kg of iron(III) oxide. Assuming that the reaction goes to completion (ie, no leftover iron(III) oxide) what is the percent purity of iron(III) oxide in the original sample?

2007-07-21 04:41:16 · 3 answers · asked by whazzup451 1

a) The carbon dioxide of the atmosphere, being a nonmetallic oxide and acid anhydride, has a low solubulity in rain water but produces a slightly acidic solution. Write an equilibrium equation for the dissolution of carbon dioxide in water and identify the acid that is formed.

b) Calcium carbonate, the major component of limestone, is slightly soluble in water. Write an equilbrium equation showing the slight solubility of calcium carbonate in water.

c) Write a Bronsted equation for the weak acid formed in part a, showing how it produces hydronium ion in aqueous solution.

d) Using LeChateliers principle, explain how the weak acid formed in rainwater causes the dissolution of calcium carbonate. the consequence of this reaction contributes to the degree of hardness in underground and surface water supplies and also accounts for the formation of stalagmites and stalactites.

2007-07-21 04:12:36 · 2 answers · asked by Anonymous

gold in color when owner does so many good deeds. I saw one woman with the bracelet in gold color and another where it had turned brassy. Is there a more natural explanation?

2007-07-21 04:11:26 · 4 answers · asked by jlc 2

2007-07-21 03:23:05 · 4 answers · asked by jowelle d 1

2007-07-21 03:20:19 · 3 answers · asked by jowelle d 1

2007-07-21 03:07:33 · 8 answers · asked by linifer74 1

what is the purity product of urotropin?

the therapeutic action of this product depends on what compound?

2007-07-21 02:56:45 · 2 answers · asked by Anonymous

I have been married for 11 years and have worn my solid gold engagement and wedding ring continuously. I woke up one morning to find both of my rings had turned to silver. This is not a hoax, it is true. I have had no cemicals near them and I've always worn the same branded rubber gloves. The only thing that is different was that I started taking the Yasmin (birth control pill) a week ago. The color is a dull silver like they've come out of a christmas cracker. I've kept them off my finger for 2 days now and the colour is now a horrid copper. May be they'll turn back to gold I don't know but can anybody explain. And please no pathetic answers.

2007-07-21 02:33:30 · 5 answers · asked by Anonymous

2007-07-21 01:32:24 · 5 answers · asked by >D_ConTradictor< 4

2007-07-20 23:33:29 · 5 answers · asked by Sisith A 1

2007-07-20 22:49:57 · 12 answers · asked by ABHILASH 2

2007-07-20 21:55:41 · 1 answers · asked by John Michael C 1

2007-07-20 21:24:08 · 4 answers · asked by ranjani_2710 1

Naturally occurring lead exists as four stable isotopes: 204Pb with a mass of 203.973 amu (1.480%); 206Pb, 205.9745 amu (23.60%); 207Pb, 206.9759 amu (22.60%); and 208Pb, 207.9766 amu (52.30%). Calculate the average atomic mass of lead.

2007-07-20 19:40:47 · 3 answers · asked by lulu 1

2007-07-20 19:34:01 · 12 answers · asked by quatre 1

2007-07-20 19:27:23 · 6 answers · asked by Anonymous

2007-07-20 19:00:01 · 6 answers · asked by Anonymous

I get the basics of the Nernst equation, so if anyone knows how to do this exact problem, I'd appreciate it!

Given the half reactions:
Ce^(4+) + e− → Ce^(3+) E° = 1.72 V
Fe^(3+) + e− → Fe^(2+) E° = 0.771 V

What volume of 0.36 M Ce4+ solution must be mixed with 40. mL of 0.42 M Fe2+ solution to produce a solution which produces a platinum electrode potential (relative to SHE) of 1.2455 V.?

This is what I have so far:
I know E(cell) = E(cathode) - E(anode), or E(cell)= 1.72-.771 = 0.949 V
E= E(cell) - [0.0257/n]*ln(Q) [[where .0257 is a constant equal to RT/F at 298 K]]
1.2455= 0.949 - (0.0257/1)*ln(Q)

I can solve for the reaction quotient (Q), but I don't know how I'd solve for volume from that. Any help?

2007-07-20 18:43:49 · 2 answers · asked by victoria 5

want to know about semen disorders problems and symptoms in men.

2007-07-20 18:33:32 · 8 answers · asked by ws 1

In the following reaction what is:

1. the reactant that is reduced
2. the reactant that is oxidized
3. the oxidizing agent
4. the reducing agent

2 Na (s) + Cl2 (g) --> 2NaCl (s)

2007-07-20 18:33:31 · 5 answers · asked by Ginger 1

Here are the chemicals:

1. Bismuth Carbonate
2. Aluminum+CuCl2
3. Pb(NO3)2(aq) + NaI(aq)
4.Magnesium

If you could help it'd be a lot of help, even a site where I can find these types of chemicals would be of help...thanks for your time!

2007-07-20 17:23:51 · 3 answers · asked by silent_knight_9 1

32P has a half life of 14.26 days. If you initially have 100.0g of 32P how many grams of it remain after 3 half life periods?

2007-07-20 15:57:15 · 4 answers · asked by AP 1

If anyone can help me get started on this I would greatly appreciate it. I'm lost.

2007-07-20 15:50:04 · 1 answers · asked by AP 1

2007-07-20 15:44:51 · 2 answers · asked by Tammy W 1

1) If you spilled some BASE while in the lab room, what substance could you use to stop its action? (Give its chemical name & formula).

2) If you spilled some BASE while your kitchen, what substance could you use to stop its action? ( Give its common name).

2007-07-20 15:43:06 · 6 answers · asked by Anonymous

2007-07-20 15:17:12 · 2 answers · asked by dagre3003 1

Question #1: Copper has a density of 8.92 g/mL. What mass of copper will occupy 45 mL? What volume of copper will have a mass of 1.0 kg (1000g)? Use significant digits.

I got these answers, but am not sure if they're correct:
Part 1: 4.0 X 10^2 g
Part 2: 110 mL

Question #2: The density of quartz was determined by adding a weighted sample to a graduated cylinder containing 56.3 mL of water. After submerging the quartz, the water level was 68.2 mL. The mass of the quartz was 36.5 g. What was the density of the quartz. Use significant digits.

I got this answer, but again I'm not sure if it's correct:
3.07 g/mL

Thanks for any help you can give me!

2007-07-20 14:52:24 · 3 answers · asked by Steven M 3

Given the reaction:
BaCl2(aq) + K2CrO4(aq) BaCrO4(s) + 2KCl(aq)
Calculate the following.

(1) The grams of BaCrO4 that can be obtained from 100.0 mL of 0.373 M BaCl2.

(2) The volume of 1.00 M BaCl2 needed to react with 50.0 mL of 0.413 M K2CrO4 solution.

2007-07-20 14:40:48 · 3 answers · asked by lulu 1

Do diagrams that show unit cells with atom/s located at each lattice point actually represent the "centre" of atom/s? When we see pictures of unit cells the lattice points are spread apart and you get 3-D box like constructions. As there are no spaces between atoms in unit cells I assume that we are actually looking at atom centres for each lattice point?

2007-07-20 13:01:34 · 1 answers · asked by Gideon 1