Chemistry - December 2007

Is it the same theory on how snow is white?

2007-12-31 18:32:20 · 9 answers · asked by edysalt 3

2007-12-31 18:31:29 · 7 answers · asked by tony 1

appreciate it if anyone answers

2007-12-31 18:19:54 · 3 answers · asked by tony 1

determination of sulphur in albumin and egg yolk

2007-12-31 18:16:44 · 2 answers · asked by sakura 1

Numeric Response

25. If the hydronium ion concentration is 10M, what is the pH of the solution?

26. If [OH] = 1 10M, what is the pH of the solution?

27. What is the pH of a solution with a concentration of 0.01M hydrochloric acid?

Short Answer

28. Use the information below to calculate ΔH for the following reaction: 2NO(g) NO(g)

N(g) + 2O(g) 2NO(g) ΔH = 67.7 kJ
N(g) + 2O(g) NO(g) ΔH = 9.7 kJ

29. What is the hydronium ion concentration if the pH is 3.7?

30. What is the pH if the hydronium ion concentration is 6.8 10M?

Problem

31. How much heat is absorbed by 15.5 g of water when its temperature is increased from 20.0°C to 50.0°C?

32. How much energy is released when 500g of water vapor at 1000C condenses to form liquid water at the same temperature?

2007-12-31 16:28:59 · 4 answers · asked by Kathy Miller 1

How do you know if a compound is polar or nonpolar??
ie: TeF4

2007-12-31 16:12:08 · 4 answers · asked by sarah 2

what is its taste?

2007-12-31 12:03:59 · 3 answers · asked by Anonymous

explain in terms of atomic structure why cesium has lower first ionization energy than rubidium

2007-12-31 11:55:55 · 2 answers · asked by anon reigns 3

1. 4NaCl + 2Cu(NO3)2  4NaNO3 + 2CuCl2
-Precipitate: 2CuCl2

2. 4NaCl + 2Fe(NO3)2  4NaNO3 + 2FeCl2
-Precipitate: 2FeCl2

3. 4NaCl + 2Ag(NO3)2  4NaNO3 + 2AgCl2
-Precipitate: 2AgCl2

4. 2Na3PO4 + 3Cu(NO3)2  6NaNO3 + Cu3(PO4)2
-Precipitate: Cu3(PO4)2

5. 2Na3PO4 + 3Fe(NO3)2  6NaNO3 + Fe3(PO4)2
-Precipitate: Fe3(PO4)2

6. 2Na3PO4 + 3FAg(NO3)2  6NaNO3 + Ag3(PO4)2
-Precipitate: Ag3(PO4)2

7. 2NaOH + Cu(NO3)2  2NaCO3 + Cu(OH)2
-Precipitate: Cu(OH)2

8. 2NaOH + Fe(NO3)2  2NaCO3 + Fe(OH)2
-Precipitate: Fe(OH)2

9. 2NaOH + Ag(NO3)2  2NaCO3 + Ag(OH)2
-Precipitate: Ag(OH)2

10. 2NaSO4 + Cu(NO3)2  2NaNO3 + Cu(SO4)2
-Precipitate: Cu(SO4)2

11. 2NaSO4 + Fe(NO3)2  2NaNO3 + Fe(SO4)2
-Precipitate: Fe(SO4)2

12. 2NaSO4 + Ag(NO3)2  2NaNO3 + Ag(SO4)2
-Precipitate: Ag(SO4)2

2007-12-31 11:15:52 · 3 answers · asked by Joey G 2

I know that a paraffin is an alkane, but what exactly does the n mean?

2007-12-31 11:11:22 · 7 answers · asked by humby 2

http://i2.tinypic.com/7wgbeyo.jpg

2007-12-31 11:04:25 · 1 answers · asked by anon reigns 3

The salts used were Iodized salt, Lite Salt (it's a salt with Potassium chloride and Iodine combined) Sea salt and table salt.
Iodized salt melted the ice cube faster than all the others..but why?

2007-12-31 10:54:02 · 3 answers · asked by Anonymous

Silver ions can be precipitated from aqueous solutions by the addition of aqueous chloride:
Ag+(aq) + Cl- (aq) -> AgCl(s)

Silver Chloride is virtually insoluble in water so that the reaction appears to go to completion. How many grams of solid NaCl must be added to 25 mL or 0.366Mol AgNO3 solution to completely precipitate the silver?

2007-12-31 09:42:50 · 2 answers · asked by Anonymous

2007-12-31 09:32:15 · 4 answers · asked by who? 1

Thanks in advance for the help. I got project on mercury and the element's like confusing me.
What is mercury's electron configuration?
Some sites have the configuration as this: [Xe] 4f14 5d10 6s2
and others as this: [Xe]6s24f145d10.
WHICH IS CORRECT? x_x;

2007-12-31 09:28:02 · 4 answers · asked by Anonymous

but the isotope has 50 neutrons...why?

2007-12-31 09:18:08 · 3 answers · asked by Me<3JB 2

is this not the process for culling out the plasma from blood for example?

2007-12-31 08:53:04 · 4 answers · asked by Anonymous

We're doing an elements project, I have to type about 3 pages about my element, which is oxygen. then I have to make a 4-6minute video, powerpoint presentation, etc. I'm thinking about the video, but I dont know what to do, I think it would be stupid, whats your advice?

2007-12-31 08:51:06 · 2 answers · asked by Aaron C 3

2007-12-31 08:37:21 · 3 answers · asked by NoName 3

2007-12-31 08:36:44 · 11 answers · asked by joe e 1

2007-12-31 08:28:47 · 4 answers · asked by schang820 2

Which of the following substances has the higest entropy?

a. steam
b. ice water
c. liquid water
d. crushed ice

2007-12-31 08:20:48 · 3 answers · asked by Anonymous

Given the redox reaction:

2+ 3+
2Cr(s) + 3Cu (aq) --> 2Cr (aq) + 3Cu(s)

Which reaction occurs at the cathode in an electrochemical cell?

a- reduction of Cu(s)
2+
b- reduction of Cu (aq)
c- oxidation of Cr(s)
3+
d- oxidation of Cr (aq)

thanks in advance =)

2007-12-31 08:18:14 · 2 answers · asked by person 3

Given the equation for the overall reaction in a lead- acid storage battery:
discharge>>
Pb(s) = PbO2 + 2H2SO4(aq) <---------->2PbSO4(s) + 2H2O(l)
<
Which occurs during the charging of the battery?

a- The concentration of H2SO4 increases and the number of moles of H2O(l) decreases.
b- The concentration of H2SO4 increases and the number of moles of Pb(s) decreases.
c- The concentration of H2SO4 decreases and the number of moles of H2O(l) increases.
d- The concentration of H2SI4 decreases and the number of moles of Pb(s) increases.

thanks in advance =)

2007-12-31 08:12:33 · 2 answers · asked by person 3

In the reaction:
H2O + H2O <--> H3O+ + OH-

The water is

a- a proton donor, only
b- a proton acceptor, only
c- both a proton donor and a proton acceptor
d- neither a proton donor nor a proton acceptor

thanks in advance =)

2007-12-31 08:06:03 · 3 answers · asked by person 3

Which species is produced when a hydrogen atom is oxidized?

a- H:H (notice two dots)
b- H:- (notice two dots)
c- H. (notice one dot)
d- H+ (notice no dots)

thanks in advance =)

2007-12-31 08:01:27 · 2 answers · asked by person 3

The equation below represents the reaction for a lead-acid battery.
discharge>>
Pb + PbO2 + 2H2SO4 <----------> 2PbSO4 + 2H2O
< Which species is oxidized during the discharge of the battery?

a- PbSO4
b- H2SO4
c- PbO2
d- Pb

thanks in advance =)

2007-12-31 07:54:23 · 2 answers · asked by person 3

2007-12-31 07:49:35 · 3 answers · asked by Em 3

Given the reaction at equilibrium:
N2(g) + 3H2(g) <--> 2NH3(g) = heat
At constant temperature, which changes would produce a greater yield of NH3(g)?

a- decreasing the pressure and decreasing the concentration of N2(g)
b- increasing the pressure and decreasing the concentration of N2(g)
c- increasing the pressure and increasing the concentration of N2(g)
d- decreasing the pressure and increasing the concentration of N2(g)

thanks in advance =)

2007-12-31 07:46:04 · 2 answers · asked by person 3

Buffer solution:
5 mL 0.20M CH3COOH
5 mL 0.20M NaCH3COO
upon addition of strong acid: 0.05 mL 1.0M HCl

Calculate pH of solution.

2007-12-31 07:17:39 · 3 answers · asked by olympus-sza 1