Chemistry - March 2007

1. How is the graph of mass loss against time related to the rate of the reaction between calcium carbonate and hydrochloric acid?
(The graph shows that when the molecular is smaller in size the reaction rate tends to be faster at the beginning however the same at the end.)

2. How does decreasing the particle size of calcium carbonate affect the reaction?

3. Suggest another experimental arrangement that could be used to monitor the rate of reaction.

(thanks)

2007-03-13 22:07:16 · 3 answers · asked by mayeham7 1

2007-03-13 22:07:08 · 1 answers · asked by yahooligan! 3

A 1.800 g sample of octane, C8H18 was burned in a bomb calorimeter whose total heat capacity is 11.66 kJ/degrees C. The temperature of the calorimeter plus contents increased from 20.21 degrees C to 28.25 degrees C.

What is the heat of combustion per mole of octane?
delta H combustion = ???? kJ/mol

This is what I did and it was wrong:

q= C m delta T

so.... 11.66 kJ/C (1.8 g) 8.04 degrees C
= 168.7 k

168.kJ 114.22858 g (molecular wgt.)
---------- x ------------------------------------ = 10705.75
1.8 g 1 mol C8H18


That was the wrong answer....

So I don't know how to do the problem..

2007-03-13 21:57:26 · 2 answers · asked by piccolo504 2

I NEED A DESCRIPTION FOR INSTANCE TELL ME THE STEPS WHICH ARE DONE IN METALLIC BONDING FOR A PARTICULAR METAL - PREFERABLY NOT MAGNESIUM AND SODIUM THANX

2007-03-13 21:39:05 · 4 answers · asked by Anonymous

2007-03-13 21:36:33 · 1 answers · asked by elsadeikahmed 1

are stable atoms radioactive- i want to know do you know the atoms that do not bond are they radioactive and what are the advantages of an atom being stable?
thanx

2007-03-13 21:17:40 · 3 answers · asked by Anonymous

2007-03-13 21:13:43 · 13 answers · asked by ronald c 1

2007-03-13 21:04:54 · 8 answers · asked by ronald c 1

2007-03-13 21:03:16 · 5 answers · asked by ronald c 1

2007-03-13 20:57:37 · 1 answers · asked by Anonymous

2007-03-13 20:23:24 · 2 answers · asked by bernadette e 1

2007-03-13 19:41:18 · 1 answers · asked by Anonymous

2007-03-13 19:19:11 · 3 answers · asked by Anonymous

Balance the following equation for an oxidation-reduction reaction occurring in an acidic solution:
HCl + H2C2O4 + MnO2(s) → MnCl2 + CO2(g) + H2O
(all numbers are subscripts)
All i need is the sum of the coefficients

2007-03-13 19:02:12 · 4 answers · asked by heather m 2

if the density of a gas is 1.2 g/L at 745 torr and 20 C

2007-03-13 18:47:33 · 1 answers · asked by Anonymous

2007-03-13 18:36:49 · 3 answers · asked by alathief 1

im doing an experiment on the polarity of substances. and i need to validate water as a universal substance. if water and ethanol are both polar...y iznt ethanol considered to be universal solvent too...what makes water special?

2007-03-13 18:33:06 · 3 answers · asked by Anonymous

I really need your help.. I want to know more about the Gaia Theory... coz I need to make my reaction about that theory...

2007-03-13 18:31:47 · 2 answers · asked by vianney_girl 1

Can anyone tell me if I am right. The charge or oxidation number for Na2S4O6? Is the charge/oxidation number for the Sulfur 10+
thanks

2007-03-13 18:29:07 · 2 answers · asked by Boo Radley 4

2007-03-13 18:23:55 · 4 answers · asked by -jAiVe- 1

Which of the following designations, polar or nonpolar, are correct for the given compounds below ?



a) CO2 : nonpolar

b) PCl3 : nonpolar

c) CH3CH2OH : polar

d) PCl5 : nonpolar

2007-03-13 18:20:48 · 4 answers · asked by Anonymous

2007-03-13 18:20:16 · 1 answers · asked by -jAiVe- 1

2007-03-13 18:19:27 · 1 answers · asked by -jAiVe- 1

through the ideal gas law.
800 torr-->1 atm
25 C--> 298 K
R= .0821
PM=dRT

2007-03-13 18:18:54 · 3 answers · asked by Anonymous

2007-03-13 18:18:00 · 2 answers · asked by Anonymous

2007-03-13 18:16:11 · 1 answers · asked by Anonymous

2007-03-13 18:15:52 · 2 answers · asked by Anonymous

The measured percentage ionic character of the bond in real diatomic molecules varies from zero % (purely covalent) to 100% (purely ionic). True of False

2007-03-13 18:15:13 · 2 answers · asked by You6789 1

2007-03-13 18:12:22 · 2 answers · asked by -jAiVe- 1

Electrons in an unfilled shell are called_______ electrons.
Let M stand for any alkali metal atom. In the reactions of alkali metals with water
2M (s) + 2H2O (l)> _______ (aq) + H2 (g)
Mg (s) + H2O (g)> ________ (s) + H2 (g)

Let M stand for any alkaline earth metal atom larger than Mg. In the reactions of M with water
M (s) + 2H2O (l)> _______ (aq) + H2 (g)

2007-03-13 18:05:10 · 3 answers · asked by lsubetty 2