Chemistry - September 2007

2007-09-26 10:55:25 · 2 answers · asked by minilew 1

I don't understand red ox. I mean... all the numbers are supposed to balance and okay, fine, but what do they all mean? how do the molecules have charges and then change charges? and they're not even charges, they're "hypothetical" charges. so what does that mean? it's a potential to be charged +2 and they lose that potential in the reaction? and how does it all tie into reactions in general? do all reactions involve redox? and if we just balance any equation, like we were doing before we learned redox, was that all wrong because we didn't take into consideration the "hypothetical" charges? I'm sooo confused. :(

2007-09-26 10:24:51 · 3 answers · asked by Anonymous

2007-09-26 10:21:23 · 11 answers · asked by Anonymous

NaCl is soluble in hot and cold water.
C6H5COOH is soluble in hot water but not cold water.
AgBr is insoluble in water.

How do I seperate this mixture of these three solids?

2007-09-26 10:13:43 · 3 answers · asked by xxiangel 2

A patient receives iodine-131 as a medical treatment on Monday, Sept. 11 at 11:00 am. On what date will only 1/4 of the original sample still be radioactive?
and can someone explain too...thanx =D

2007-09-26 09:56:36 · 5 answers · asked by brownies<33 2

Identify oxidizing agent, reducing agent, the substance being oxidized, and the substance being reduced. Explain.

a) HCl (g) + NH3 (g) ---> NH4Cl (s)

b) SiCl4 (l) + 2 H2O (l) ---> 4 HCl (aq) + SiO2 (s)

Thank you!

2007-09-26 09:38:04 · 1 answers · asked by Anonymous

2007-09-26 09:33:34 · 4 answers · asked by XoSexierDenYewXo 1

What type of forces are there between molecules of chloroethene? are there van der waals?
Also, what are two uses of PVC? thanks again.

2007-09-26 09:28:36 · 3 answers · asked by Anonymous

skin
glucose
veggie oil
hair
RNA
sucrose
butter
fingernails
H(2)SO(4)
HNO(3)
gelatin
molasses
vinegar

2007-09-26 09:20:29 · 2 answers · asked by Marissa 2

Hi can someone please tell me how to draw a dot and cross diagram for this? i cant seem to figure it out. thanks.

2007-09-26 09:16:10 · 2 answers · asked by Anonymous

2007-09-26 09:05:31 · 3 answers · asked by Miss. Worried 1

HCl
DNA
Starch
KOH
Sodium Chloride

2007-09-26 09:03:21 · 4 answers · asked by Marissa 2

hi, please can someone help - what is the bond angle in OF2?? thanks!

2007-09-26 08:55:11 · 3 answers · asked by Anonymous

I have horrible heartburn.. What food might i have lying around that contains a base to neutralize this?

2007-09-26 08:44:05 · 5 answers · asked by Anonymous

You notice that when water boils over it causes of the gas burner to turn bright orange. How would you explain the appearance of a color in the flame?

2007-09-26 08:37:39 · 5 answers · asked by student00 2

What is the symbol for carbon monoixide, and what reacts to make it? Also is anything else made by the reaction?

2007-09-26 08:27:09 · 14 answers · asked by night rider 2

2007-09-26 07:28:59 · 3 answers · asked by Justin T 1

how do you find oxidation numbers when you are given an equation etc..i know we're supposed to use the laws but sometimes i get confused. I am trying to find the oxidation number for AgNO3 and Fe(HCO3)2, can someone help ??

2007-09-26 06:28:27 · 4 answers · asked by Sskli D 1

2007-09-26 06:10:54 · 1 answers · asked by Cassie 2

its to help me with my science work :)

2007-09-26 06:09:10 · 3 answers · asked by Cassie 2

I'm being asked to find the wavelength in nm of three possible electronic transitions of Lithium. The three energies given are 178 kJ/mol, 370 kJ/mol, and 375 kJ/mol,

I can't figure out how to get the wavelength from this. I tried using L=hc/E but I end up getting something crazy

2007-09-26 05:44:18 · 3 answers · asked by Steven S 2

the numbers are supposed to be subscripts*

2007-09-26 05:40:33 · 1 answers · asked by cr_unk420 1

"2-Hydroxypropanoic acid was dissolved in D2O and an n.m.r spectrum of the solution was taken. Predict, with reasons, the splitting patterns observed in this spectrum"

Any ideas welcome.

2007-09-26 05:36:47 · 5 answers · asked by C4 Snake 3

found small brown vial labeled opo caymorium (not sure of spelling on last word). What is it and what is it used for?

2007-09-26 05:17:51 · 1 answers · asked by kk 1

2007-09-26 05:09:13 · 1 answers · asked by lana l 1

1Calculate the number of moles in 58.2 g of Se. SIG. FIG.

2Calculate the number of moles in 1.43x1022 NO2 molecules. SIG. FIG.

3Calculate the mass (in g) of 6.16 moles of H2O. SIG. FIG.

4Calculate the number of moles in 86.2 g SO3. SIG. FIG.

5Calculate the number of oxygen atoms in 20.6 g SO3. SIG. FIG.

I normally wouldn’t ask someone to do hw for me but right now I have no other choice since I need the time to study math If you help me fine ill give you five stars.

2007-09-26 04:58:57 · 2 answers · asked by Anonymous

Write the compound formulas for each of the following pairs and the name of the compound formed when the elements or radicals combine.

a) Mg^+2 + OH^-1

b) K^+1 + PO_4^-3

c) Cu^+2 + S^-2

d) N^+5 + O^-2

2007-09-26 04:58:05 · 1 answers · asked by lana l 1

4469.6 g of 10% H2SO4 mixed with 1047 g of 45% KOH and 70 L of water (total volume is ~75L), should give a pH of around 2.....however in real life I get a pH of around 1.5-1.6....what is going on here?

Additional Details

1 second ago
4469.6 grams of 10% H2SO4 mixed with 1047 grams of 45% KOH and 70 L of water (so total volume is ~75L), calculated should give a pH of around 2.....however in real life I get a pH of around 1.5-1.6....what is going on here????
>>>>>>>>>>>>>>>>>>>>>>
The calculations are:

4469.6 grams of 10% H2SO4 = 446.95 g/98g per mole = 4.561 moles of H2SO4, 2 protons per mole = 9.122 moles of H+

1047 grams of 45% KOH = 471.15g/56 g per mole = 8.41 moles of OH-



9.122 – 8.41 = 0.712 moles of protons present

à Final volume of solution is around 75L

0.712/75 = 0.00949 moles of H+ present (per litre)

pH = -log[H+]

pH = 2.02



sure a small difference would occur between theory and the real world, but please, this is a pH calcuation

2007-09-26 04:54:45 · 4 answers · asked by Anonymous

How many different constitutional isomers are there with the formula: C4H8ClF.

I do not understand how to figure this out. Please help!

2007-09-26 04:52:19 · 3 answers · asked by polly 1

formula of the hydrate is CaSO4 2H2O Calcium sulfate

2007-09-26 04:51:28 · 1 answers · asked by forlaniz3 2