Chemistry - March 2007

2007-03-09 23:16:12 · 6 answers · asked by ice i 1

2007-03-09 22:45:36 · 6 answers · asked by blubbablub 1

for synthesis and reaction .

2007-03-09 22:38:09 · 1 answers · asked by Anonymous

2007-03-09 21:05:24 · 4 answers · asked by ? 1

It says that a student obtained the following data from a reaction between a zinc strip and a copper II sulfate solutioin. WHat mass of copper would be produced?

initial mass of zinc 15.42g
final mass of zinc 14.15g

2007-03-09 19:43:38 · 6 answers · asked by Eric J 1

Why is that when Pepsi is poured in a small amount, it is in dark brown color and when it is a large amount , it is in black color ?
Does it has something to do with chemical properties?

2007-03-09 19:37:58 · 3 answers · asked by kasperpro 1

One of my students (for a science fair project) has suspended two sharpened pencils in a salt water solution (water and table salt) connected to a 9-volt battery, one pencil to positive and one to negative. He claims that the bubbles that form on the pencil tips is chlorine. Is there any truth to this? If so, what is the reaction that is taking place? How does it work?

2007-03-09 19:09:26 · 4 answers · asked by max c 1

2007-03-09 19:07:50 · 1 answers · asked by vel 1

The recommended dose of iodine-131 is 4.20 mCi/kg body weight. How many microcuries of iodine-131 are needed for a 30.0 kg patient?

2007-03-09 18:54:48 · 2 answers · asked by orange_crush_05 6

Calculate [ H + ] of a 0.330 M solution of Hydroxylamine HONH2
Kb = 1.10e-8

2007-03-09 18:26:25 · 6 answers · asked by raindrops414 1

i dont know what is the meaning combustion

2007-03-09 18:20:45 · 7 answers · asked by judah_ebarle 1

Hello- I am having difficulty making Cu2(OAc)4(H2O)2 ,
what percantage of copper should I use in relation to salt and vinegar?
Thanks,

2007-03-09 18:10:04 · 3 answers · asked by Anonymous

a) Calculate the mass in g of the compound Cs2S in 89 g of a 17.0% solution.

b) A 0.553 m3 of a gas originally at 125 oC must be reduced to a volume of 0.435 m3 at constant pressure. To what Celsius temperature must the sample be adjusted?

c) The reaction
2 Sb + 3 Cl2= 2 SbCl3
has a 62.3% yield. If 436 g of SbCl3 is obtained, what mass in g of Cl2 reacted?

thx...

2007-03-09 17:56:38 · 1 answers · asked by godrics 2

Which of the following has/have the electron configuration [Ne] 3s2 3p6?
i. S2-
ii. Cl
iii. Ar
iv. K+
v. Ca2+

p/s: wat does [Ne] stand for?

2007-03-09 17:52:08 · 3 answers · asked by godrics 2

2007-03-09 17:39:26 · 5 answers · asked by FaceFullofFashion 6

40.2 g of A2 reacts with 11.5 g of B2 to form A2B. What is the ratio of the molar mass of A to the molar mass of B?

2007-03-09 17:37:19 · 1 answers · asked by godrics 2

Hey, can you set it up like an algabraic equation and set it equal to zero? For H (subscript 2)CO.
H2 +C? + O = 0
1+(2) + C? + (2-) = 0
(2+) + C? + (2-) = 0
0 + C? =0
C?=0
so the charge for Carbon would be 0?
Does this make sense or has Chemistry driven me crazy?
thanks

2007-03-09 17:37:12 · 2 answers · asked by Boo Radley 4

My teacher said theres something that made it arranged like that

2007-03-09 17:19:20 · 6 answers · asked by Anonymous

the carbon in NaCO (subscript 3)
Na is 1+ O3 is -6 (3x-2)? then the Carbon would be 4+??????

2007-03-09 17:06:33 · 2 answers · asked by Boo Radley 4

please help...do I double the 2- for Oxygen since there are 2 of them? So 4- and 4+ for C so it would be 0?

2007-03-09 16:53:41 · 6 answers · asked by Boo Radley 4

of carbon and sulfur in the following compounds:

CO
CH(subscript 4)
SO
SCl(subscript 2)
thanks if you can help me. I need to figure out a lot of them, but I need an example first.

2007-03-09 16:39:45 · 3 answers · asked by Boo Radley 4

2007-03-09 16:18:00 · 9 answers · asked by myra f 1

Can they be differentiated?

2007-03-09 16:16:04 · 5 answers · asked by raito 1

2007-03-09 16:15:13 · 2 answers · asked by myra f 1

DMSO - Dimethyl sulfoxide is widely used for dissolving wide range of polar and non polar compunds? What is the basis for this property

2007-03-09 15:44:05 · 2 answers · asked by Rajagopal SV 1

a. 5.00x10^24
b. 3.00
c. 2.90x10^25
d. 1.81x10^24
e. 4.00

2007-03-09 15:41:17 · 4 answers · asked by harry p 1

Calculate [ OH - ] of a 0.220 M solution of Pyridine C5H5N Kb = 1.70e-9

2007-03-09 15:26:09 · 2 answers · asked by stargazer 2

which of the following statements are true?


a) For an acid H-A : the greater the electronegativity of A, the stronger the acid HA

b) For an acid H-A : the stronger the H-A bond, the stronger the acid H-A

c) HBr is a stronger acid than HF

d) H2SO3 is a weaker acid than H2SO4

e) HClO is a stronger acid than HBrO

f) For carboxylic acids : the greater the electronegativities of the atoms in the group bonded to the carboxyl group, the stronger the acid

2007-03-09 15:26:07 · 6 answers · asked by stargazer 2

What is [ OH - ] for a solution where pH = 6.60?

2007-03-09 15:25:43 · 6 answers · asked by stargazer 2

Which of the following are conjugate acid-base pairs ?


a) HClO and HCl
b) HClO4 and ClO4-
c) HCl and Cl -
d) H2O and OH -
e) H2SO4 and HSO4-

2007-03-09 15:25:40 · 2 answers · asked by stargazer 2