Chemistry - August 2007

2007-08-09 01:14:02 · 2 answers · asked by Anonymous

Consider 100.0-g samples of two different compounds consisting only of carbon and oxygen.Once compound contains 27.2 g of carbon and the other has 42.9 g of carbon. How can these data support the law of multiple proportions if 42.9 is not a multiple of 27.2?

2007-08-09 01:08:29 · 3 answers · asked by s.weiss 1

2007-08-08 21:39:17 · 3 answers · asked by Anonymous

2007-08-08 21:35:08 · 7 answers · asked by Anonymous

Which of the following is an example of octet expansion?

1. CIF3 (tri-fluoro-iodo methane) 2. ClF (clorine and flourine) 3.Cl2F 4. IS6

2007-08-08 21:15:55 · 1 answers · asked by Anonymous

1. Distinguish between a strong and weak electrolyte with reference to the degree of dissociation into ions.

2. Ionic compounds can dissociate into ions. Under what conditions all ionic compounds will conduct electricity?

3. Under what conditions ionic compounds cannot conduct electricity? And explain the difference.

4. Describe how electrolytes conduct electricity?

2007-08-08 21:05:21 · 1 answers · asked by Light 3

2007-08-08 20:24:55 · 2 answers · asked by mirian77 2

2007-08-08 19:58:55 · 2 answers · asked by Anonymous

Given the data
(1) N2 (g) + O2 (g) to 2NO (g) delta H = +180.7kJ
(2) 2NO (g) + O2 (g) to 2NO2 (g) delta H = -113.1kJ
(3) 2N2O (g) to 2N2 (g) + O2 (g) delta H = -163.2kJ
use Hess Law to calculate delta H for the reaction: N2O (g) + NO2 (g) to 3NO (g)

2007-08-08 19:48:30 · 1 answers · asked by nick_zz 1

2007-08-08 19:29:42 · 2 answers · asked by vamsi k 1

If 350 mg of a radioactive element decays to 250 mg in 36 hours, what is its half-life?

2007-08-08 18:35:21 · 3 answers · asked by Anonymous

Most multiply-charged anions have less-charged versions stable in more acidic solutions, including the chromate ion CrO4--. However, most such anions are partially acidified simply by adding one or more hydrogen atoms to them, such as HCO3-, HPO4-- and H2PO4-, HSO4-, and so on. The partially acidified chromate ion is different in this respect, where two of the basic Cr2O4-- ions combine to form a Cr2O7-- ion rather than two HCrO4- ions implied by the older name for the dichromate ion "bichromate." Who, when, and how was this anomalous behavior discovered and what chemical consequences does it have?

I am also looking for references for more detailed info. These must be provided for "best answer."

2007-08-08 17:55:29 · 4 answers · asked by devilsadvocate1728 6

2007-08-08 17:45:56 · 2 answers · asked by Anonymous

2007-08-08 17:45:51 · 1 answers · asked by Anonymous

2007-08-08 17:45:47 · 1 answers · asked by Anonymous

a.fission
b.fusion
c.radiation belts
d.all of the above

2007-08-08 15:36:31 · 6 answers · asked by diba a 1

the two densest elements are in scientific competition with each other as to which one is actually the densest. What gives?

2007-08-08 15:32:02 · 4 answers · asked by explorer4x4guy 2

a. the mass number changes
b. the atomic number changes
c.the atomic number remains the same
d. the number of neutrons remains the same

2007-08-08 15:30:44 · 2 answers · asked by diba a 1

a. Toluene
b. m-xylene
c. p-xylene
d. Benzoic acid

2007-08-08 15:22:52 · 1 answers · asked by dave b 2

1.Increases
2. increases then decreases
3. Decreases
4. Remains constant

2007-08-08 14:13:04 · 2 answers · asked by jane C 1

Petrol = Gas
Parafin?
Diesel?
Aviation fuel?

2007-08-08 14:08:01 · 10 answers · asked by BLUE MOON 3

I always get confused when it comes to naming acids and writing their formulas. If you could please explain how to name acids and write their formulas that would be really appreciated. Thanks.

2007-08-08 10:32:07 · 2 answers · asked by Jade 3

i got my test back and i dont know why i got this wrong??

can you please help me?
thanks

A researcher has an unknown biological compound that she knows is a triprotic acid. She weighs out 2.143 grams of the unknown acid, dissolves it in water, adds an indicator, and titrates it to neutrality using 81.99 mL of 0.1195 M NaOH. What is the molecular weight of the acid?
answer:_______ AMU

2007-08-08 10:24:36 · 3 answers · asked by Anonymous

And, is H2S hydrogen sulfide?

2007-08-08 09:42:47 · 5 answers · asked by nightowl 2

Hello. I need to know the reaction product of the electrolysis of metallic chromium. Would it be enough to oxidize it to a +6 oxidation state and become chromic acid, or just chromic oxide or perhaps chromium hydroxide? Thank you.

2007-08-08 09:30:11 · 1 answers · asked by Jo Blo 2

A 2.00-kg metal object requires 5020 J of heat to raise its temperature from 20.0°C to 40.0°C. What is the specific heat capacity of the metal?

126 J/(kg • °C)

106 KJ/(kg • °C)

126 cal/(kg • °C)

142 kcal(kg • °C)

2007-08-08 09:04:15 · 4 answers · asked by Anonymous

a. burning coal
b. storing batteries
c. air conditioners
d. automobiles

2007-08-08 06:34:59 · 12 answers · asked by chato r 1

2007-08-08 06:30:24 · 5 answers · asked by DDT 2

Which is an example of a compound whose individual elements are very dangerious, but when combined make a useful compound?

table salt

sodium metal

chlorine gas

2007-08-08 06:07:23 · 2 answers · asked by yod 1

[AIF4]-
[Cu(NH3)4]2+
[FeCDTA]3+

I would really like to see the process to get the answer to this. This question is on a practice test.

2007-08-08 03:14:47 · 3 answers · asked by Falcur 1