Chemistry - September 2007

It's actually supposed to be quite simple, but I've been searching everywhere for the past hour and I couldn't find anything exact on it. How do I calculate the abundance of isotopes? I would really appreciate it if someone responded. Thank you.

2007-09-11 04:19:57 · 1 answers · asked by Anonymous

What element is oxidized in the chemical reaction
3Cu + 8HNO3 → 3Cu(NO3)2 + 2NO + 4H2O?

a. Cu
b. H
c. N
d. O
e. H2O

2007-09-11 04:06:28 · 3 answers · asked by Anonymous

1. the speed of the reaction depends on the reaction conditions describe how each of the following affects the speed of a reaction

a particle size of reactants
b concentration of the reactants
c tempreature of the reactants

Please help

cpkid

2007-09-11 04:03:17 · 8 answers · asked by Captain Awesome (Superhero) 2

2007-09-11 03:39:13 · 1 answers · asked by Anonymous

1) Given: 0.209g vapor
757mmHg
100.5 degrees celsius or 373.5 K
Volume of flask 151mL
2)2.82g gas
639mL
27degrees or 300K
1.00 atm ???
I am not sure for one thing how to find the R (ideal gas law)
M=mRT/PV

2007-09-11 03:29:59 · 1 answers · asked by luawai 1

Bought 100% apple juice in a plastic 96 oz container. Drank some, no problem. A few days later I took the cap off and it was totally carbonated. Smelled like Alcohol too. Poured it out into the sink, and it fizzed like Ginger ale. Can this occur naturally, or did some "house guest" play a sick joke?

2007-09-11 03:15:49 · 3 answers · asked by Kelly A 4

For the complete redox reactions given here, (i) break down each reaction into its half-reactions, (ii) identify the oxidizing agent, (iii) Identify the reducing agents

(a) 2Sr + 02 ------> 2SrO
(b) 2 Li + H2 ------> 2LiH
(c) 2Cs + Br2 -----> 2CsBr
(d) 3Mg + N2 ------> Mg3N2

2007-09-11 01:03:48 · 3 answers · asked by Anonymous

I'm thinking that the gas NH3 is one of the products, but I don't know how to get there. Also, when heated, all of the reactants seem to evaporate, so I'm not sure what the products are.

Possibly NH3 and CO2?

Can somebody please help me with the balancing?

2007-09-10 18:58:35 · 1 answers · asked by Tony K 2

two flasks are connected with a stopcock. the first flask has a volume of 5 liters and contains nitrogen gas at a pressure of .75 atm. the second flask has a volume of 8L and contains oxygen gas at a pressure of .125 atm. when the stopcocl between the flasks is opened and the gases are free to mix what will the pressure be in the resulting mixture?

2007-09-10 18:12:15 · 1 answers · asked by hii 1

if I know the substance has a vapor pressure of 40 torr at 673 C and 100 torr at 736 C?
please tell me the formulas!!!!!!!
the unit is K

2007-09-10 18:06:00 · 1 answers · asked by siying 1

chemstry

2007-09-10 17:52:57 · 3 answers · asked by karen m 1

Can you please tell me the solution and how you did it I have basically no knowlege on writing chemical equations for chem...

What compound do these two ions form?
AL^3+ and O^2-

Thank you.

2007-09-10 17:46:04 · 5 answers · asked by billf39 2

Hi,
I'm doing a lab and it consists writing a procedure on how to seperate mixture of sodium chloride, silicon dixoide and calcium carbonate.
Well I figured out how to separate sodium chloride from the other ones. But how do i separate calcium carbonate and silicon dioxide?

2007-09-10 17:17:52 · 2 answers · asked by Jiwoo S 1

i dont really get this addition/ minus as well as division and multiplication

please show me the steps and explain it to me in simple English
and please solve these questions
500 - 3.7
500. -83.35

2007-09-10 17:16:55 · 1 answers · asked by Anonymous

thanks

2007-09-10 17:12:09 · 2 answers · asked by Anonymous

in a reaction between magnesium and oxygen, the only product is 80.0 grams of magnesium oxide. how many grams of magnesium were burned?

2007-09-10 17:06:04 · 5 answers · asked by hii 1

ethane gas (C2H6) burns in air to form carbon dioxide and water. how many grams of carbon dioxide are produced for each 8.00 grams of water produced?

2007-09-10 17:04:27 · 1 answers · asked by hii 1

The method of preparation for an aqueous solution calls for 5.0 grams of anhyrdrous sodium sulfate, Na2SO4. The sodium sulfate available is crystalline hydrated sodium sulfate, NaSO4 * 10 H2O. How many grams of this hydrated compound should be used in place of the anhydrous compound when preparing the reagent? FW of Na2SO4 is 119.05 g/FW, MW of water is 18.02 g/mol. Hint: the number of moles of crystalline hydrated sodium sulfate must equal the number of moles of anhydrous sodium sulfate

2007-09-10 16:27:26 · 1 answers · asked by Jon P 1

i'm ordering tape( invisible tape/Transparent tape) for tape some sterling silver chain. will the non acid-free tape damage my silver chain?

2007-09-10 12:25:03 · 2 answers · asked by carol 1

the density of a piece of metal alloy is 4.35 g/cm cubed. what is the volume of 53.7 kg of this metal? density = mass/volume

2007-09-10 12:18:21 · 4 answers · asked by xoo_christina_77 1

Lithium has two naturally occuring isotopes. Lithium-6 has an atomic mass of 6.015 amu, and lithium-7 has an atomic mass of 7.016 amu. The average atomic mass of lithium is 6.941 amu. What is the percentage of naturally occuring lithium-7?

How do I work this problem to find the answer.

2007-09-10 11:57:04 · 1 answers · asked by Average Joes 4

2007-09-10 11:45:46 · 11 answers · asked by seekerjan 1

Describe the difference in what is being communicated in the following symbols:
P4 and 4P\
Cl2 and Cl
Hg (l) and Hg (g)
H2O2 and H2 + O2
NaCl (l) and NaCl (aq)
Mg and Mg 2+

2007-09-10 11:39:38 · 1 answers · asked by Anonymous

help plz!!!!!!

2007-09-10 11:36:35 · 4 answers · asked by shima 1

what are the correct names for the chemical compounds

Cr(OH)3

K2CrO4

KMnO4

Sr(CN)2

Ca(NO3)2

2007-09-10 11:18:09 · 3 answers · asked by yahooanswers23 1

2007-09-10 10:52:00 · 1 answers · asked by Anonymous

Of course an element is made of many atoms, but be more descriptive.

2007-09-10 10:50:31 · 6 answers · asked by Average Joes 4

I know one way they differ is containing a different number of neutrons in their nucleus. What's another way they differ? Is it that they could have a different amount of electrons outside the nucleus?

2007-09-10 10:39:55 · 5 answers · asked by Average Joes 4

Tell me anything you know about this question. It would be greatly appreciated!

2007-09-10 09:50:09 · 1 answers · asked by robert johnson 2

Descride how gold can be seperated from a mixture of sand and dirt. What characteristic property of gold allows it to be separated in this way?

2007-09-10 09:46:50 · 5 answers · asked by Anonymous