Chemistry - November 2007

I know you would use a red for an acid and a blue for a base but why....

2007-11-14 10:36:06 · 2 answers · asked by Anonymous

2007-11-14 10:34:09 · 5 answers · asked by Anonymous

1.Why are some chemical symbols so different from the names of the elements that they present?
2. Why do some symbols have one letter, some have two letters, and some have three letters?

2007-11-14 10:23:16 · 4 answers · asked by Quinn H 2

2007-11-14 10:19:13 · 2 answers · asked by Anonymous

1) nitric acid + potassium iodide ------> potassium nitrate + nitrogen monoxide + water

2007-11-14 10:02:44 · 1 answers · asked by Caramel 2

2007-11-14 10:00:24 · 5 answers · asked by kaynat A 2

A 6.5 L sample of nitrogen at 25±C and 0.76
atm is allowed to expand to 13.0 L. The tem-
perature remains constant. What is the ¯nal
pressure?
1. 0.063 atm
2. 0.38 atm
3. 0.75 atm
4. 0.12 atm
5. 3.0 atm
0

2007-11-14 09:55:59 · 3 answers · asked by Anonymous

The combustion of acetylene gas is represented by this equation:

2C2H2 + 5O2 --------> 4Co2 + 2H2O2
(sorry that subscripts don't work)

a) How many grams of CO2 and grams of H2O are produced when 52.0g C2H2 burns?

b)How many grams of oxygen are required to burn 52.0g C2H2?

c)Use the answeres from A and B to show that this equation obeys the law of conservation of energy.

MY ANSWERS
a)175.78g CO2
35.98g O2
211.76g total

b)6.14g O2

c) ?

WHAT I DID
* means multiply, / means fraction

a) How many grams of CO2 and grams of H2O are produced when 52.0g C2H2 burns?

5.20g C2H2 * (1 mol C2H2 / 26.04g C2H2) * (4mol CO2 / 2mol C2H2) * (44.01g Co2 / 1 mol CO2) = 175.78g CO2

52.0gC2H2 *( 1 mol C2H2 / 26.04g C2H2) * (2 mol H2O / 2 mol C2H2) * (18.02g H20 / 1 mol H20) = 35.98g O2

= 211.76g total

b) How many grams of oxygen are required to burn 52.0g C2H2?

52.0g C2H2 * (1 mol C2H2 / 26.04g C2H2) * (5 mol O2 / 2 mol C2H2) * (32.00g O2 / 1 mol O2) = 6.14g O2

2007-11-14 09:55:01 · 2 answers · asked by Emily A 3

2007-11-14 09:45:57 · 5 answers · asked by kevin s 1

for example, if you had C10H16O
how could you tell from that what the smell would be like?

2007-11-14 09:42:24 · 2 answers · asked by jenners92 1

The nitric oxide is then oxidized to nitrogen dioxide.

2NO + O2 --> 2NO2

Calculate the standard reaction enthalpy for the reaction above (as written) using the following data:
N2 + O2 --> 2NO deltaH = 180.5
N2 + 2O2 --> 2NO2 deltaH = 66.4

All answers in negative:
1. 114.1
2. 520.2
3. 975
4. 690.72
5. 128.2
6. 100.3
7. 252.4

2007-11-14 09:34:47 · 2 answers · asked by Anonymous

Can someone please help me with this this probablem involves 2 circles. One containing E (energy) on the top and h and v on the bottom. Now, the other is C (speed of light which is 3.00 X 10 to the 8th power and wavelenght and frequency on the bottom. Please please help, I have a test on this stuff tomorrow...I get the concept...but really need help...I know how to do it when it involves one circle but not when it involves tow circles. :(

2007-11-14 09:32:42 · 3 answers · asked by svothfan 2

I need to find the products for 2,2-Dimethyl-1-propanol. I know that a rearrangement occurs to give the more stable carbocation. However, from then on, how do I know which hydrogen I should pluck off to get the products? I can see 3 sources, the two methyl group and the CH2. Any help please? Also, it's not just for this question, I've been doing others and face this delimma also. Is there a rule to determine which C I should form the double bond with, if there are multiple carbons which I can take the hydrogen off of?

2007-11-14 09:21:53 · 2 answers · asked by Reimei 2

Which of the following are oxidizing agents ?

a) H2

b) F2

c) Br2

d) Cu

e) C

2007-11-14 09:10:56 · 1 answers · asked by Peter G 3

Are flame tests valuable for detecting metal ions present in a mixture of metal ions?

Also, in class we did flame tests with sodium and potassium and then used cobalt glass to see the flame also. I don't understand why? How can this help identify the two elements?

2007-11-14 09:02:04 · 4 answers · asked by love*pink 3

We need to feed an aquarium with CO2, if we heat CACO3 to liberate CO2, the cold CaO could absorb CO2 from the air and be reheated to liberte more CO2?

2007-11-14 08:44:37 · 3 answers · asked by espiral 2

2007-11-14 08:40:23 · 3 answers · asked by Tammy 1

if a typical aspirin tablet contains 325 mg aspirin, how many tablets could you prepare from 2.1 g???

2007-11-14 08:28:45 · 9 answers · asked by sweetgirl78228 2

2007-11-14 07:03:23 · 6 answers · asked by yodave 1

Can anyone tell me who first discovered cumene/cumene process and was it named after them or what not?

2007-11-14 07:01:57 · 2 answers · asked by Ravioli 2

Characteristics of alpha, beta and gama radiation when they are shot thru a magnetic field?

2007-11-14 06:56:12 · 2 answers · asked by Apo A 1

What trends were used to first classify the elements of the periodic table? What trends were discovered after the elements were classified in the periodic table?

It's for a chemistry assignment and I've been working on it for an hour and still have no idea. Any help would be greatly appreciated! 10th grade answers please =) I cannot find any good websites with the information, and the text book barely explains it.

2007-11-14 05:41:06 · 2 answers · asked by Ya 5

Is it possible to conduct electrolysis experiments with the 120V mains? I'm sure that if I do that carefully, I'll get a rather good yield of H2 and O2 with the water...

2007-11-14 05:07:34 · 2 answers · asked by Anonymous

1) Always polar.
2) Always non Polar
3)Depending on the arrangement of outer atoms, this molecule could be polar or nonpolar.

2007-11-14 04:36:03 · 3 answers · asked by Anonymous

2007-11-14 03:16:46 · 4 answers · asked by Anonymous

2007-11-13 19:00:36 · 1 answers · asked by Christian 1

What are the units of Molarity? How many grams of NaOH are needed to make 0.5 L of .25 M NaOH Solution? How do I do this problem?

2007-11-13 16:57:00 · 1 answers · asked by Christine O 1

Methanol, CH3OH, can be made by combining gaseous carbon monoxide and hydrogen gas.
In one experiment 2.07 g of H2 is mixed with 16.90 g of CO.


How many grams of CH3OH will be produced?

2007-11-13 15:04:28 · 2 answers · asked by matt b 1

If a 0.060 M sample of Co(N03)2 gave an absorbance of 0.29 at 500 nm in a 1 cm cell. What is the cobalt concentration of a solution giving and absorbance of 0.14 in the same cell at the same wavelength

2007-11-13 14:57:23 · 1 answers · asked by babye 1

Which of the following molecules can form hydrogen bonds with other molecules of the same kind:

1) CH3F
2) CH3NH2
3) CH3OH
4) CH3Br

Explain your choice(s)

2007-11-13 14:54:16 · 1 answers · asked by To-the-Stars 4