Chemistry - April 2007

If copper metal is a mixture two isotopes Cu-63 mass=62.9298 u and Cu-65, mass=64.9279 u. Calculate the % abundances if the molar mass of copper is 64.546 g/mole.

2007-04-09 10:45:15 · 2 answers · asked by mrfame1017 3

The computer writes electron configurations in the form, for Fe for example, [Ar]4s(2)3d(6)

which we would write [Ar]4s23d6

Using the computer format give the electron configuration for


Cu2+

2007-04-09 10:34:00 · 1 answers · asked by Christie 1

Any ideas and chemical formulas are appreciated

2007-04-09 10:27:41 · 1 answers · asked by allison_x 1

The carbon dioxide that is exhaled by astronauts who are on a space shuttle is scrubbed by pumping air through canisters of lithium hydroxide, LiOH. THe chemical equation for this reaction is 2 LiOH + CO2 = Li2CO3 + H2O
a) WHat mass of a carbon dioxide can 1.00 kg of lithium hydroxide absorb?
b) What mass of lithium carbonate, Li2CO3, is produced?
c) Explain why this reaction limits the amount of time that astronauts can spend in space?
Thanks to anyone who can help me with these questions as I am doing this from home and seem to be stuck on this Chapter.

2007-04-09 08:57:49 · 4 answers · asked by flowers4eden 1

2007-04-09 08:51:35 · 6 answers · asked by roxysurf611 1

it is an element of the perodic table.

2007-04-09 08:49:49 · 10 answers · asked by motofreek_09 1

I have 2 sets of data for NaCl in soils and one is in mg/kg and the other is in ppm, but don't I need to know how much a cm3 of my soil weighs to be able to convert it?

2007-04-09 08:46:25 · 6 answers · asked by amateurgrower 3

I need help in finding the electron configuration for Ni 4+

2007-04-09 08:43:21 · 1 answers · asked by giggles9783 1

10 HI + 2 KMnO4 + 3 H2SO4 ---> 5 I2 + 2MnSO4 + K2SO4 + 8 H2O

According to the balanced equation above, how many moles of HI would be necessary to produce 2.5 mol of I2 starting with 4.0 mol of KMnO4 and 3.0 mol of H2SO4?

Can anyone please help us? We've been struggling for hours trying to solve this problem... we've taken an educated that the anwer would be 5.0 moles but we're not really sure... if anyone could please help us and show us step by step how to solve this problem, we would really appreciate it, thank you all in advance!

2007-04-09 08:33:25 · 1 answers · asked by Hola Lola! 2

CH4+O2 -----> CO2+H2O

what are the multiples of this reaction?
and how many kilos of methane do you need to release 890MJ of energy, when the burningtemp. of methane is 890kJ/mol?

Please help me with this, I've tried SO many times, and just seem to get stuck over and over again. Big hug for the one that solves this.

2007-04-09 08:22:44 · 2 answers · asked by fredriqa 2

When the equation is properly balanced with the smallest ratio of integer coefficients, which of the following statements are true ?
(For statement e, assume the amount of given reactant reacts completely.)
a) The coefficient of propane is 1

b) The coefficient of oxygen is 5

c) The coefficient of carbon dioxide is equal to that of oxygen

d) The coefficient of water is four fifths that of oxygen

e) 4 mole of propane produces 16 mole of water

f) 4.5 mole of oxygen reacts with 0.9 mole of propane

2007-04-09 08:12:20 · 3 answers · asked by JD 1

a) This is an example of an elimination reaction

True or false

Pb2+(aq) + 2I−(aq) → PbI2(s)
b) This is an example of a precipitation reaction



c) The product is an ionic compound

CH3Cl + OH− → CH3OH + Cl−
d) This is an example of a substitution reaction



e) Double bonds are formed in the product

2007-04-09 08:11:22 · 1 answers · asked by JD 1

A 40 mL sample of .25 M KOH is added to 60 mL of .15 M Ba(OH)2. What is the Molar concentration of OH- (aq) in the resulting solution? (Assume that the volumes are additive)

How should I start of this problem? I attempted to use an ice table, eq expressions, but no luck.... can anyone walk me through the steps please! Thank you so much for all you help!

2007-04-09 08:08:23 · 1 answers · asked by Hola Lola! 2

compare the structures and properties of carbohydrates with those of proteins.

2007-04-09 08:07:37 · 3 answers · asked by TheGreatest 3

For a science fair project

2007-04-09 08:05:49 · 2 answers · asked by Anonymous

I am wondering where my thinking is going wrong here.

They say for a process to happen, the total entropy change has to either stay the same or increase. If this is the case, what happens when water freezes. The number of ways the atoms can be arranged decreases, yet the process still occurs. Why is it?

2007-04-09 07:55:31 · 5 answers · asked by Anonymous

2007-04-09 07:37:09 · 2 answers · asked by watercurves 6

i need to find the formula for tetraamminedichlorocobalt(III) chloride

2007-04-09 07:36:30 · 5 answers · asked by giggles9783 1

what alkali is present in bleach??

2007-04-09 07:31:29 · 4 answers · asked by bitterhoney 1

Can anyone tell me how to solve this problem? I don't need the answer I just need to know how to do it... like should we convert from grams to mols? and then what? I'm really not sure how to even start out the problem ... please help!!! Thank you!

2007-04-09 07:28:00 · 3 answers · asked by Hola Lola! 2

yeah i get the if glucosem is present after adding the bendict solution (including hot bath)it turns deep yellow or red......what does that mean if it's deep yellow?
what does it mean if it's red?


plus after that when you add the HC1 and the baking soda....what then? how does that tell me wether or not it has sucrose these procedures are confusing and it's killing me!!!!

here's where i got the procedure...
http://www.soinc.org/events/foodscience/Sucrose_NATC_.pdf

2007-04-09 07:21:13 · 1 answers · asked by Nery C 1

in terms of the type of bonding and/or the forces inbetween the molecules.

Pentane:- B.P= 36
Methylbutane:- B.P=28
Dimethylpropane:- B.P=9

2007-04-09 07:14:49 · 1 answers · asked by aka sweety 1

explain these observations by reference to the type of bonding present and/or the forces between organic molecules.

Butane:- molecular mass= 58 B.P= -1
Propanone:- molecular mass=58 B.P= 56
Ethanoic acid:- molecular mass=60 B.P= 118

2007-04-09 07:11:44 · 3 answers · asked by aka sweety 1

determine the value and sign of AH for the following reaction:
2H-F → H-H + F-F

2007-04-09 06:40:59 · 1 answers · asked by JULIO C 1

ok so I have to find a " mystery word " by filling in certain letters by answering questions as you will see...I've already gotten the word (it is equation) , but Im having trouble with naming the 3 questions


1st Problem - The arrow in a chemical equation means "yields" or "__."
(7th letter) *Which is E

3rd problem - Combination of chemical symbols used to represent a compound
(5th letter) *Which is U

7th question - Used to the right of formulas to tell the solution class
(5th letter) *Which is O

2007-04-09 06:38:26 · 1 answers · asked by Anonymous

2007-04-09 05:57:26 · 1 answers · asked by cait 2

explain how you reached your conclusion

2007-04-09 05:56:39 · 3 answers · asked by cait 2

Why would metal have any smell at all? Are particles of copper released into the air?

2007-04-09 05:55:14 · 2 answers · asked by presidentrichardnixon 3

a. glucose in the bloodstream. b. glycogen in the liver. c. glycogen in the muscles. d. cellulose in the cell walls. e. oligosaccharides in the glycocalyx

2007-04-09 04:55:04 · 2 answers · asked by Anonymous

Approx. what mass of CuSO4 - 5H2o (250 g mol-1) is required to prepare 250 mL of 0.10M copper(II) sulfate solution?

2007-04-09 04:51:41 · 2 answers · asked by boopi 2