Chemistry - April 2007

A gas storage tank has a spring closure that maintains a constant pressure while permitting the volume to adjust to changes in temperature. What will be the volume of the gas if 25.0 L of a gas at 20.0 degrees C is heated to 30.0 degrees C?

2007-04-10 13:46:18 · 1 answers · asked by kickitup21 1

1. Write a complex word equation listing the reactants and predicted products. Water will be a product!

2. Write a balanced formula equation for your double replacement reaction. Predict which compound will form a precipitate and indicate this in the equation using the symbol, (s), following the chemical formula. Water will be a product!

3. Calculate the molar mass of each reactant and product.

4. Calculate the number of moles in 2.00 g of the precipitated product.

5. Determine the mass of each reactant required to make 2.00 grams of your precipitate.

2007-04-10 13:41:56 · 2 answers · asked by lilprincess_2good4u 1

Predict the effect of each of the following changes on the initial rate of the reaction and give the reason for your prediction.
a. increasing the volume of the reaction vessel at constant temperature
b. adding a catalyst
c. increasing the temperature

2007-04-10 13:38:06 · 2 answers · asked by Moohlah. 2

I need help with this question, and it is multiple choice but which one is the answer? Please reply soon! IT is due tomorrow and i am not sure.

a.) the pressure increases
b.) the pressure does not change
c.)the pressure decreases
d.) the pressure cannot be predicted

2007-04-10 13:04:09 · 5 answers · asked by K T 3

Calculate the [H+] for 0.50 M HCN solution. K subscript a=4.0*10^-10
Calculate the % dissaciation.

I have no idea how to do this, so if you could walk me through it step by step, and provide an answer at the end it would be much appreciated.

Also, how would I solve it if it asked me to calculate the [H3O+] or the [OH-]


thanks soo much!

2007-04-10 10:53:33 · 2 answers · asked by Remy 5

I need to know the structure of methanol, butane && glucose. Such as a straight chain, a ring or a branch chain.
Also I need to compare && contrast methanol, butane && glucose. Which means to find their similiaraties between all && how they are different.
PLEASE HURRY, my project is due fairly soon.
&& don't get any info. wrong :D

2007-04-10 10:34:44 · 3 answers · asked by radioxrockstar 2

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+

2007-04-10 10:33:21 · 2 answers · asked by Beth F 1

Na3[IrCl6]

2007-04-10 10:17:19 · 1 answers · asked by mark u 1

What is the oxidation state and d electron count (number of d electrons) for the metal ion in the following coordination complex ?

[Mn(CO)5Cl]

2007-04-10 10:15:53 · 2 answers · asked by nataliya05 1

2007-04-10 09:04:02 · 5 answers · asked by Anonymous

2007-04-10 08:52:27 · 16 answers · asked by Anonymous

a) what do you understand by the terms strong acid and weak acid and how is the species H3O+ classified?
b) what is meant by the pH of solution, stating how this quantity is defined and the approximation that is usually made in applying it to a solution. how may pH be calculated for a solution of concentration c of
i) a monoprotic stong acid and
ii) a monoprotic weak acid with an acidity constant Ka?
hence calculate the pH of 0.05 mol dm-3 HCL solution and 0.05 mol dm-3 ethanoic acid solution (Ka = 1.8 * 10-5 mol dm-3)
c)describe with a diagram how the acidity constant of a weak acid may be determined by a pH titration and explain the theoretical basic for this determination
d) give two reasons why it is difficult to measure the acidity constant for polyprotic acids such as polypeptides.

2007-04-10 08:20:58 · 4 answers · asked by jes 1

the 2 is a roman numeral

2007-04-10 08:18:29 · 1 answers · asked by mike m 1

2007-04-10 07:58:13 · 3 answers · asked by PB_Smith 1

can you list them?

2007-04-10 07:39:58 · 5 answers · asked by Anonymous

(a) As the atomic number increases for d-block transition elements, electrons are in general added to an inner d orbital

(b) Metals in high oxidation states tend to be good reducing agents

(c) A common oxidation state of manganese is +4

(d) Going across a period the atomic radii changes a great deal.

(e) As the atomic number increases for the lanthanides and actinides transition metal elements,
electrons are added to an inner d orbital.

2007-04-10 07:27:52 · 1 answers · asked by owaifkahlfkjh 2

2007-04-10 06:50:48 · 3 answers · asked by Anonymous

N2 + 3H2 -> 2NH3 In the above equation, if you want to increase the amount of product to 312 mol NH3, can you use stoichiometric calculations to find out how much of each reactant to use?

2007-04-10 05:56:51 · 2 answers · asked by Anonymous

2007-04-10 05:55:17 · 5 answers · asked by parul b 2

What is the oxidation state and d electron count (number of d electrons) for the metal ion in the following coordination complex ?


[Cr(H2O)6]I3


You must enter two numbers with one and only one space between them
i.e., +2 4 would be a correct answer format.

2007-04-10 05:39:27 · 2 answers · asked by woj87marta 1

How do you identify salts from non-salts in chemical compounds? Please be very basic.

2007-04-10 05:18:16 · 4 answers · asked by warren d 2

The N2F2 molecule can exist in either of the following two forms:

............F
.......... /
....N=N
..../
F

F.........F
..\......./
...N=N

What is the hybridization of N in the molecule?
Which structure has a dipole moment?

2007-04-10 05:16:08 · 2 answers · asked by sky_blue 1

2007-04-10 04:39:06 · 5 answers · asked by taixsantixlove 3

2007-04-10 04:33:58 · 6 answers · asked by Stephanie S 1

2007-04-10 03:37:50 · 1 answers · asked by Brian D 1

assume that you counted continually 24 hours a day.

2007-04-10 03:18:16 · 7 answers · asked by tina r 1

a) Explain what is meant by a positive ion test.
B) Describe two types of cahnges that demonstrate a positive test.


2. Suposse that you were asked to determine whether an ion was present in a soulution and how much ion was present

a)Compare amounts of the precipitate that you would expect if you added barium cholorise to two solutions that contained different amounts of sulfate ion.

B) Compare the color intensity that you woule expect if you added potassium thiocynate to two solutions that contained different amounts of iron (III) ion.

2007-04-10 02:15:09 · 1 answers · asked by Anonymous

Ammonium is NH4 made by the protonation of Nitrogen. How come when you add a proton to Nitrogen it does not become an isotope of Oxygen...since it has the same proton number. How come Ammonium is not OH4?

2007-04-10 01:45:07 · 5 answers · asked by jos c 1

Where can I buy Potassium Cyanide in India?

2007-04-10 00:37:22 · 10 answers · asked by Anonymous

running out? - that's part of the above question !

2007-04-10 00:04:26 · 9 answers · asked by hazra b 1