Chemistry - February 2007

Which of the following solids has electrons that are mobile, and how do you know? Potassium iodide, camphor, zinc, silicon dioxide

2007-02-24 09:57:53 · 2 answers · asked by untilyoucamealong04 3

The heating curve of water shows it gaining kinetic energy and potential energy, but not at the same time. I also know that sublimation can occur where ice will gain potential energy without first gaining kinetic. Does this mean that ice and water are turning to steam at any time and that the curve is just a basic guideline? Does this cahnge any calculations in q=mc(delta)t?

2007-02-24 09:53:35 · 1 answers · asked by MooMooKowz 1

a) a chemical reaction MAY occur when molecules of reactants collide together. explain why it is that at a given temperature, only a certian proportion fo molecules react together on collision.
b) why do N2 and H2 react very slowly in the gaseous phase, but much more rapidly in teh presence of an iron catalyst?

2007-02-24 09:42:38 · 3 answers · asked by MZ 1

Is one comparing the relative strengths of covalent and ionic bonds when comparing the relative melting points of potassium iodide and camphor? Why?

2007-02-24 09:33:22 · 3 answers · asked by untilyoucamealong04 3

2007-02-24 09:18:36 · 4 answers · asked by Yo mama 2

Water is a polar solvent whereas TTE is not very polar. How does polarity influence the solubility of potassium iodide, camphor, zinc, and silicon dioxide?

2007-02-24 09:16:49 · 2 answers · asked by untilyoucamealong04 3

Predict the electrical conductivity (high or low) of each substance in the liquid state: Potassium iodide, Camphor, Zinc strip, and Silicon Dioxide

2007-02-24 09:07:16 · 1 answers · asked by untilyoucamealong04 3

2007-02-24 09:06:55 · 3 answers · asked by Professor 1

The hardware store has many choices. What is the science behind it? Is one better than the other?

2007-02-24 09:04:06 · 3 answers · asked by Anonymous

i have troubles with chem hw

2007-02-24 08:53:54 · 3 answers · asked by Marree 2

Why is the effect on reaction rate of introducing a catalyst much greater than the effect of increasing concentration?


Thanks!

2007-02-24 08:53:51 · 4 answers · asked by MZ 1

2007-02-24 08:53:39 · 3 answers · asked by Gc 1

Predict the electrical conductivity (high or low) of each substance in the solid state: Potassium iodide, Camphor, Zinc strip, and Silicon Dioxide

2007-02-24 08:50:09 · 1 answers · asked by untilyoucamealong04 3

I am totally mixed up about moles. The question is How many moles of CO2 are produced when 2.09 mol of octane is burned?
The answer is 16.7moles of CO2 but how do we get that answer?

2007-02-24 08:49:46 · 1 answers · asked by Toothie 2

a) For the reaction CO2(g) → CO2(s)
entropy increases


b) For the reaction NaCl(s) + H2O(l) → NaCl(aq)
entropy increases


c) Molecules Cl2(g) should have have greater
entropy per mole, than molecules of SO2(g)


d) If entropy decreases for a certain process, the entropy of the universe increases

2007-02-24 08:35:47 · 2 answers · asked by Gemini 2

For the reaction whose reactants and products are:



reactants: NH3 (g) O2 (g)


products: N2 (g) H2O (g)


calculate the standard entropy change (J/mol-K).

The answer depends on how you balance the equation. For this question balance the equation using the smallest ratio of WHOLE numbers.

2007-02-24 08:34:06 · 1 answers · asked by Gemini 2

For iodine the enthalpy of sublimation is 62.0 kJ/mol. The entropy of sublimation is 145 J/(K mol).
Calculate the sublimation temperature (Kelvin).

2007-02-24 08:33:34 · 3 answers · asked by Gemini 2

I've always loved the chemical reaction of vinegar and baking soda, so please give me as much info as you can!

2007-02-24 08:12:27 · 3 answers · asked by Science Guy 2

not the planet mercury

2007-02-24 08:02:46 · 3 answers · asked by Anonymous

2007-02-24 07:53:33 · 2 answers · asked by Anonymous

2007-02-24 07:36:02 · 2 answers · asked by Anonymous

2007-02-24 07:01:03 · 7 answers · asked by answersonyahoo 2

Question Details:The species are [ C2H5NH2] , [ H]+, [ C2H5NH3] +, [Cl]- and [OH]- Please help me in solving this problem related to acids and bases. Thanx in advance...

2007-02-24 07:00:12 · 1 answers · asked by Anonymous

2007-02-24 06:54:33 · 5 answers · asked by lani g 1

2007-02-24 06:37:58 · 1 answers · asked by henry f 2

What is the pH of a buffer made from 0.11 M hydrocyanic acid and 0.20 M sodium cyanate? Use the Ka value from a table and the Ka expression for the acid "reacting".

I have tried to do this problem, but I still got it wrong:

(4.9e-10) * (.20/.11) = 8.91e-10
pH= -log(8.91e-10) = 9.05

If anyone can help or let me know what mistake I have made, your response will greatly be appreciated.

2007-02-24 06:37:01 · 2 answers · asked by ash 1

For each of the following functions determine whether the function is an eigenfunction of the d/dx and d^2/dx^2 operators, and if so determine the eigenvalues:
a) e^(-ax^2)
b) cos(bx)
c) e^(ikx) where i= sqrt (-1)

2007-02-24 06:12:05 · 1 answers · asked by Anonymous

2007-02-24 06:11:59 · 3 answers · asked by henry f 2

2007-02-24 05:57:57 · 1 answers · asked by Anonymous

im having a little trouble with my nuclear equation chemistry homework. These are the 2 problems:
beta decay of 165,61Pm and beta decay of 152,54Xe. I'm pretty sure the answers are: Pm--->0,-1B+165,62Sm and Xe---->0,-1B+152,55Cs. Please help!

2007-02-24 05:51:18 · 3 answers · asked by Alex P 1