Chemistry - April 2007

ok, i have to do a project for chemistry and i have to do something about scuba and gas laws. i need to make a pamphlet to let the divers know what to be aware of. and i dont get it, plz help....this is what i have to do...using the words "the bends" and "oxygen toxicity" and "barotrauma" write something to make aware of the gass laws that affects diving such as charles' laws, boyle's law, etc...

2007-04-11 17:05:38 · 4 answers · asked by lil aj 1

also need to know why it is important to maintain equivalent proportions or reagents in the reaction

2007-04-11 17:04:08 · 2 answers · asked by Anonymous

if the diff between two levels of an atom is 3.03 x 10^19 J, what color of light is associated with this transition?

2007-04-11 16:57:53 · 3 answers · asked by crazymonkey 1

2007-04-11 16:51:25 · 0 answers · asked by ? 1

Calculate the difference, ΔH-ΔE=Δ(PV) for the combustion reaction of 1 mole of propane. (Assume standard state conditions for all reactants and products.)

2007-04-11 16:49:42 · 1 answers · asked by Anonymous

2007-04-11 16:48:32 · 5 answers · asked by igotaonetonrodeo 1

2007-04-11 16:45:42 · 2 answers · asked by ? 1

I'm so lost... I'm trying to study for my chem quiz so I don't fail and I don't understand this stuff at all... anyhow... this is in the context of discussing rates of chemical reactions, and assuming hypothetical experimentally determined values.

2007-04-11 16:43:08 · 2 answers · asked by ssmith 3

What are the factors that make the reaction to have two different products.

Any help is appreciated.

2007-04-11 16:36:52 · 0 answers · asked by alanis118 1

(***using the bohr theory***)
What is the binding energy of the 3rd electron in Lithium?

2007-04-11 16:35:27 · 1 answers · asked by Anonymous

Two of my answers below are incorrect, but I don't know which ones.

1) CuO(s) + HCl(aq)---> CuCl2(aq) + H2O(l)
My answer: double replacement

2) 2Al(s) + 3Br2(g) ---> 2AlBr3(s)
My answer: combination

3) 2C2H2(g) + 5O2(g) ---> 4CO2(g) + 2H2O(g)
My answer: combustion

4) Pb(NO3)2(aq) + 2NaCl(aq) ---> PbCl2(s) + 2NaNO3(aq)
My answer: double replacement

5) 2Mg(s) + O2(g) ---> 2MgO(s)
My answer: combustion

6) Fe2O3(s) + 3C(s) ---> 2Fe(s) + 3CO(g)
My answer: single replacement

7) C6H12O6(aq) ---> 2C2H6O(aq) + 2CO2(g)
My answer: decompostion and combustion

8) BaCl + KCO ---> BaCO + 2KCl
My answer: double replacement

Some answers in the answer bank, but I didn't use are:
-Decomposition
-Single replacement and combination
-Double replacement and single replacement
-Other type of reaction
-Combination and decomposition
-Oxidation reduction reaction
-Combination and combustion.
-Neutralization

THANKS VERY MUCH.

2007-04-11 16:22:29 · 3 answers · asked by Anonymous

What is common about the oxidation numbers of the elements in the following molecules: H2, P4, S8, C60?

*The numbers above are all the subscripts of the elements.

2007-04-11 16:17:14 · 1 answers · asked by ╦╩╔╩╦ O.J. ╔╩╦╠═ 6

2007-04-11 16:10:23 · 1 answers · asked by regan w 1

******When the equation
__C8H16 + __O2 → __CO2 + __H2O
is correctly balanced using the smallest whole number coefficient, the coefficient of O2 is

a) 1
b) 8
c) 12
d) 16

******Given the balanced equation:

4Al(s) + 3O2(g) 2Al2O3(s)

What is the total number of moles of O2(g) that must react completely with 8.0 moles of Al(s) in order to form Al2O3(s)?

********A gas occupies a volume of 444 mL at 273 K and 79.0 kPa. What is the final kelvin temperature when the volume of the gas is changed to 1880 mL and the pressure is changed to 38.7 kPa?

a) 31.5 K
b) 292 K
c) 566 K
d) 2360 K

2007-04-11 16:07:35 · 3 answers · asked by anonydipity_09 3

Which of the following are true for the Crystal Field Model of an octahedral complex ion? Consider ions to be from first-row transition metals.



a) The ligands cause a splitting of energy of the 3d orbitals

b) eg orbitals are more stable than t2 orbitals

c) A large crystal field splitting energy results in a diamagnetic complex

d) The high-spin case gives maximum unpaired electrons

e) For a given ligand, Co3+ causes a greater increase in the crystal field splitting energy than does Co2+
think about the amount of coulombic attraction between the metal ion and the electrons on the ligands
and the closer the ligands, the more interaction there is with the d orbitals on the metal ion

f) Cl- causes a greater increase in the crystal field splitting enery than does H2O

g) The splitting of energy (E) of 3d orbitals occurs in the metal ion

i tired everything!! please help, thank you

2007-04-11 16:03:48 · 2 answers · asked by Anonymous

a) How many unpaired electrons are in the d-orbital splitting diagram for the octahedral complex ion of

Fe2+ high spin




b) How many unpaired electrons are in the following complex ion

Ru(NH3)6 2+ lowspin

2007-04-11 16:02:21 · 1 answers · asked by guitarx313 1

For the coordination compound [Ag(NH3)2]NO3 give the oxidation state of the transition metal followed by the the coordination number.

2007-04-11 16:01:25 · 1 answers · asked by guitarx313 1

Ideal gases A and B are in separate bottles separated by a valve. Gas A has pressure 0.3039 atm and volume 0.2700 liters and temperature 400.0 K. Gas B has pressure 0.2844 atm and volume 0.6490 liters and temperature 300.0 K. The valve is opened and the temperature is allowed to adjust adiabatically. What is the partial pressure of gas A?

Is the answer 0.08929 atm?

2007-04-11 15:59:20 · 2 answers · asked by xxbabiesue123xx 2

half reaction for the oxidation of oxalate ion to carbon dioxide in acidic solution?
overall equation for the reaction of potassium permanganate with sodium oxalate in acidic solution?

if you can help and explain these problems, it will be greatly appreciated! thanks!

2007-04-11 15:57:06 · 3 answers · asked by epikhigh121 1

other than the forest and the ocean

2007-04-11 15:44:54 · 1 answers · asked by c 2

Ideal gases A and B are in separate bottles separated by a valve. Gas A has a pressure of 329 torr and a volume of 118 cc. Gas B has a pressure of 411 torr and volume of 216 cc. The valve is opened and the temperature is held constant. What is the partial pressure of gas A?


How would you do this?

2007-04-11 15:21:51 · 5 answers · asked by xxbabiesue123xx 2

The half-life, t 1/2, of 222Ra is 4.0 days and 1.0g of this isotope is present. How much 222Ra could we expect to be present after 4.0 weeks? can you please write down how you got the answer, so i can understnad how to do it!! thanks a million!

2007-04-11 15:11:24 · 1 answers · asked by Anonymous

2007-04-11 15:07:50 · 1 answers · asked by ? 1

2007-04-11 15:05:38 · 4 answers · asked by tamy 1

Hg(HSO4)2, Au(ClO3)3, Mn(NO3)4, Sn(SCN)2, Cu2SO4 and FeC2O4.

2007-04-11 14:51:59 · 2 answers · asked by GoGoGaget...dada 1

2007-04-11 14:50:13 · 2 answers · asked by Cookies 2

Which of the following do NOT represent a possible conjugate acid-base pair?

a) SO3 and SO2
b) CO3 and CO
c) H3O and H2
d) NH4 and NH3


Thanks

2007-04-11 14:41:40 · 3 answers · asked by Bryton 1

I am having some trouble with triprotric acids, so I was hoping someone could help me. My teacher gave the following example, and I am quite stumped, any help would be appreciated.
The question is: Citric acid (C6H5O7H3) is a troprotic acid because it has three acidic hydrogen ions to donate. Write the 3 equations that would describe how citric acid would react with water and donate its hydrogen ions.

Any help you can give would be appreciated. Thanks

2007-04-11 14:37:41 · 3 answers · asked by Bryton 1

How do I plan and design an experiment to determine if barium sulphate is safe to ingest? Please leave full details because I'm really stumped. Thanks in advance for ur help!

2007-04-11 14:36:14 · 3 answers · asked by Anonymous

a) How many unpaired electrons are in the d-orbital splitting diagram for the octahedral complex ion of

Fe2+ high spin




b) How many unpaired electrons are in the following complex ion

Ru(NH3)62+ lowspin

2007-04-11 14:32:38 · 2 answers · asked by asiansenz 1