Chemistry - October 2007

Such that the concentration of a phenolphthalein indication turns bright pink? Does this mean that the acid has been completely neutralized and that the concentration is zero? Or is there still some acid left in the mixture?

2007-10-02 06:43:28 · 3 answers · asked by blueanswers 2

Ammonia(aq) + hydrochloric acid(aq)


and identify the spectator ions

2007-10-02 06:40:35 · 1 answers · asked by bumblebee 4

reactions. How is it used? please give exmples

2007-10-02 06:34:42 · 3 answers · asked by topher4193 2

2007-10-02 06:27:01 · 3 answers · asked by jnester0289 1

If a reaction carried out at 25 degrees C has a rate constant of 3.15*10^-5 1/M*s and an activation energy of 36.6 kJ/mol, what is the temperature in degrees celcius when the rate constant is 4.80*10^-4 1/M*s?

2007-10-02 06:24:25 · 1 answers · asked by Anonymous

2007-10-02 06:15:48 · 1 answers · asked by !Jeshyjellybean. 1

1) A flask contains 81.9 mL of 0.150 M Ca(OH)2. How many milliliters of 0.350 M Na2CO3 are required to react completely with the calcium hydroxide in the following reaction?
Na2CO3(aq) _ Ca(OH)2(aq) --> CaCO3(s) + 2NaOH(aq)

2) A 1.345 g sample of a compound of barium and oxygen was dissolved in hydrochloric acid to give a solution of barium ion, which was then precipitated with an excess of potassium chromate to give 2.012 g of barium chromate, BaCrO4. What is the formula of the compound?

2007-10-02 06:05:02 · 1 answers · asked by keya_na 2

I want to know how to seperate an Atom. This is a question for my chemestry class and I cant seem to find any direct and understandable information on it. If you know of any means as to how to seperate an Atom, your answer would be much appriciated...thanks!

2007-10-02 05:55:36 · 8 answers · asked by Anonymous

Calculate the final volume in mL of a solution obtained if 100.0 mL of 6.27 M NaCl is diluted to 1.81 M.

2007-10-02 05:47:14 · 1 answers · asked by mike g 1

i need help i figured out hydrochloric with mgnesuim gives 2nd order but stuck on what ethanoics order of reaction is could help me with this experiment.i am using 15cm3 of acids and 0.17g of magnesuim ribbon in an gas stringe experiment.

2007-10-02 05:38:55 · 1 answers · asked by Anonymous

i. Aluminium(s)
ii. Fe3O4(s)
iii. Al203(s)
iv. Fe(s)
v. H2O2(l)
vi. H2O(l)
vii. O2
viii. HCI

2007-10-02 05:36:44 · 1 answers · asked by virgo 1

plz help

2007-10-02 04:38:57 · 3 answers · asked by Anonymous

2007-10-02 04:37:31 · 6 answers · asked by Amy V 1

Member since: December 26, 2006
Total points: 158 (Level 1)
Points earned this week:
33% Best answer
9 answers
Joshua
S Chem - Stio help?
Have a few I just wanted to check on:

1) Potassium Sulfate contains 44.9% potassium by mass. In a 50.0g sample of potassium sulfate, the # of moles of potassium is:
A)0.287mol B)1.28mol C)1.74mol D).574mol E)2.00mol
My answer : D but think I might have divide by 2 one more time?

2) Detonation of nitroglycerian proceeds as follows:

4(C3H5O9N3)----
---->6N2+O2+10H2O

How many grams of water vapor are formed from the combustion of 5.953g of nitroglycerian?

My answer(s): 1st answer is 1.18g, second is 0.3868

2007-10-02 04:24:31 · 2 answers · asked by Reviction 1

R&D and QC

2007-10-02 03:52:53 · 1 answers · asked by zookini 1

please no web site links

2007-10-02 03:23:55 · 5 answers · asked by Becker14 1

sample is remaining after 7.5 days?



Technetium-99 decays to ruthenium-99 with a half life of 210,000y. Starting with 1.00 mg of technetium-99, how long will it take for 0.75 mg of ruthenium -99 to form?

2007-10-02 03:15:55 · 3 answers · asked by angela 1

2007-10-02 03:15:33 · 4 answers · asked by beachblondie 1

HCl+Fe->a+b
HCl+MgO->c+d
HCl+Al(OH)3->e+d
HCl+CaCo2->d+g+f

Thx

2007-10-02 03:01:39 · 2 answers · asked by Simon T 2

2007-10-02 00:49:32 · 1 answers · asked by FLO F 1

2007-10-02 00:41:30 · 4 answers · asked by Anonymous

2007-10-02 00:19:14 · 7 answers · asked by rebeca m 1

As water has the anomolous behaviour after 4 degree celsius!.
There is another element a metal which has the same behaviour. please let me know which metal is that?

2007-10-01 23:54:22 · 2 answers · asked by Anonymous

High-density polyethylene may be chlorinated by inducing the random substitution of chlorine atoms for hydrogen.

Determine the weight percent of Cl that must be added if this substitution occurs for 4% of all the original hydrogen atoms.

Express your answer with one decimal digit.

thanks, working out plz

2007-10-01 23:35:59 · 1 answers · asked by okooko 3

A resting adult requires about 240 mL of pure oxygen/min and breathes about 12 times every minute. If inhaled air contains 20% oxygen by volume and exhaled air 16%, what is the volume of air per breath? Assume that the volume of inhaled air is equal to that of exhaled air)

2007-10-01 21:47:52 · 4 answers · asked by Anonymous

2007-10-01 19:56:20 · 3 answers · asked by Anonymous

2007-10-01 19:40:05 · 3 answers · asked by coolxy 1

2007-10-01 19:30:49 · 1 answers · asked by Rajchem 2

A particular balloon can be stretched to a maximum surface area of 1257 cm^2. The balloon is filled with 3.2 L of helium gas at a pressure of 759 torr and a temperature of 292K . The balloon is then allowed to rise in the atmosphere. Assume an atmospheric temperature of 273 K and determine at what pressure the balloon will burst. (Assume the balloon to be in the shape of a sphere.) This is confusing. It doesn't look like any gas laws I know!

2007-10-01 17:39:38 · 3 answers · asked by Giant Donut 2

2007-10-01 16:59:49 · 2 answers · asked by SICK MY DUCK! 1