Chemistry - May 2007

The complete combustion of 0.40 moles of butane gas, C4H10, will

a.consume 5.2 mol O2 and produce 3.2 mol CO2.
b.consume 0.40 mol O2 and produce 0.20 mol CO2.
c.consume 2.6 mol O2 and produce 1.6 mol CO2.
d.consume 1.3 mol O2 and produce 0.80 mol CO2.
e.consume 0.80 mol O2 and produce 0.40 mol CO2.

2007-05-30 05:40:21 · 1 answers · asked by kallystarr 1

IS THE REACTION EQUILERIUM? EXPLAIN , iF NOT WILL THE REACTION PROCEED IN THE FOWARD OR REVERSE DIRECTION?

2007-05-30 05:39:10 · 3 answers · asked by mweber126 1

alternative spellings: prometheon, pfygtroeon

2007-05-30 05:38:57 · 3 answers · asked by Anonymous

If acidic or basic solutions write a balanced Equation for the reactaion a.Nh4 Br b. Kno2 c. Mg(NO3)2 d BaF2 e. K2S

2007-05-30 05:35:42 · 2 answers · asked by mweber126 1

2007-05-30 05:34:01 · 3 answers · asked by Anonymous

a. write an equation that shows how this buffer neutralixes small amountsof acid. b. write an equation that shows how this buffer neutralizes small amouts of base. c. calculate the ph of this buffer if it is 0.10 M CH3COOH and 0.10 M CH3COO - ; the Ka for CH3OOH is 1.08 x10^-5

2007-05-30 05:31:35 · 2 answers · asked by mweber126 1

How many moles of potassium bromide can be produced from the reaction of 2.92 moles of potassium with 1.78 moles of bromine gas?

2 K(s) + Br2(g) → 2 KBr(s)

a.3.56 mol
b.5.84 mol
c.1.78 mol
d.1.46 mol
e.2.92 mol

is the answer e?
thanks

2007-05-30 05:27:58 · 5 answers · asked by kallystarr 1

Synthesis
Replacement
Decompsition
Oxidation Reduction

the last one for today

2007-05-30 05:27:48 · 5 answers · asked by !it is me! 2

A skull was found and was estimated at 65 million years ago.Although the skull itself was found in a layer of rock that suggests that it is very old and initial carbon-14 dating of the surface revealed a much younger age approx. 8300 years ago suggesting that dinasours roamed th earth when humans did.

A. What is the half-life of carbon-14? How is this radioisotope different than carbon-12?

B. Carbon-14 a beat emitter forms from the bombardment of nitrogen-14 with a neutron. What is the balanced nuclear equation for the formation and decay of Carbon-14?

when answering please make sure you are positive with your answer and thank you to all who answer!

2007-05-30 05:27:12 · 1 answers · asked by MEB 2

equal volumes of 0,1 M HCl and 0,1M NaOH solutions were miced. concentration of NaCl and pH of the final solution respectively were:

correct>: 0,05 pH = 7

i tried this way. I say the volume is 1dm3. Then i multiply the concentration with 1dm3. Then i have the molar mass. 0,1mol

0,1x 2 (its two) ............= 0,1M
-------
new volume(1+1=2)

2007-05-30 05:22:24 · 4 answers · asked by Anonymous

2007-05-30 05:16:23 · 8 answers · asked by Anonymous

concentrated NaOH solition was added into water solution of ammonium sulfate. The Gas X was formed X is NH3

Why?
I was stuck here. NaOH + (NH4)2SO4 --> ? ? ?

2007-05-30 05:15:19 · 7 answers · asked by Anonymous

Balance the following equation:
_MnO2 + _HCl --> _MnCl2 + _Cl2 + _H2O
What is the coefficant of HCl?
1
2
3
4

i dont knwo how to do this!

2007-05-30 05:13:39 · 5 answers · asked by !it is me! 2

2007-05-30 05:12:26 · 5 answers · asked by Anonymous

Handling of non biodegradable waste.

2007-05-30 05:07:22 · 2 answers · asked by Anonymous

Aspirin is produced by the reaction of salicylic acid (M = 138.1 g/mol) and acetic anhydride (M = 102.1 g/mol).

C7H6O3(s) + C4H6O3(λ) → C9H8O4(s) + C2H4O2(λ)

If you mix 5.00 grams of each reactant, how many grams of aspirin (M = 180.2 g/mol) can theoretically by obtained?

a.2.83 g
b.3.83 g
c.6.52 g
d.10.0 g
e.8.82 g

2007-05-30 05:05:25 · 4 answers · asked by kallystarr 1

A time-release capsule releases a drug at a constant rate so that the concentration of the drug in the body is not so high as to damage the body nor so low as to be ineffective. The capsule has two compartments separated by an impermeable, elastic membrane. One compartment contains the drug, the other a saturated solution of sodium chloride. The outer wall of the drug compartment consists of a rigid, selectively permeable material. The wall is designed to allow only molecules of the drug to pass outward through the wall. The outer wall of the compartment containing the sodium chloride solution consists of a semi-permeable membrane. A thin, protective coating that dissolves when the capsule enters the body covers the entire capsule

What happens to the concentration of aqueous sodium chloride over time?
What process is it? What are the two functions of the elastic, impermeable membrane separating the aqueous sodium chloride solution and the drug?

2007-05-30 04:51:12 · 3 answers · asked by Anonymous

I pretty sure that the answer is no but just to be sure.

Will powedered copper react with methyl cyclohexanol at room temp? looking at the structures and a few mechanisms I made up I can't see any reason why but my chemistry's gotten a little rusty since i left uni.

BTW I'm assuming that both the copper and methyl cyclohexanol are pure, the copper is suspended in the alcohol

2007-05-30 04:47:20 · 6 answers · asked by Jamie . 1

2007-05-30 04:45:37 · 4 answers · asked by kmof6322 1

i don't know....do you???

2007-05-30 04:45:36 · 5 answers · asked by Anonymous

The combination of elements
The combination of two or more different elements
The combination of two or more similar elements
The product of compounding atoms

can you help me this is my last one and i cant find it

2007-05-30 04:43:43 · 4 answers · asked by !it is me! 2

A time-release capsule releases a drug at a constant rate so that the concentration of the drug in the body is not so high as to damage the body nor so low as to be ineffective. The capsule has two compartments separated by an impermeable, elastic membrane. One compartment contains the drug, the other a saturated solution of sodium chloride. The outer wall of the drug compartment consists of a rigid, selectively permeable material. The wall is designed to allow only molecules of the drug to pass outward through the wall. The outer wall of the compartment containing the sodium chloride solution consists of a semi-permeable membrane. A thin, protective coating that dissolves when the capsule enters the body covers the entire capsule

What happens to the concentration of aqueous sodium chloride over time?
What process is it? What are the two functions of the elastic, impermeable membrane separating the aqueous sodium chloride solution and the drug?

2007-05-30 04:42:48 · 1 answers · asked by Anonymous

Calcium reacts with fluorine gas to produce calcium fluoride. How many moles of Ca will react with 1.0 moles of F2?

a.2.0 mol
b.4.0 mol
c.1.5 mol
d.1.0 mol
e.0.50 mol

2007-05-30 04:27:37 · 3 answers · asked by kallystarr 1

Aspirin is produced by the reaction of salicylic acid (M = 138.1 g/mol) and acetic anhydride (M = 102.1 g/mol).

C7H6O3(s) + C4H6O3(λ) → C9H8O4(s) + C2H4O2(λ).

If 2.04 g of C9H8O4 (M = 180.2 g/mol) is produced from the reaction of 3.00 g C7H6O3 and 5.40 g C4H6O3, what is the percent yield?

a.68.0%
b.14.2%
c.24.3%
d.52.1%
e.21.4%

2007-05-30 03:56:45 · 2 answers · asked by Anonymous

in our science class we are given a jar with sand in it ad we are suppose to do different tests to identify it. so can u guys please help us with it?

2007-05-30 03:47:52 · 2 answers · asked by makesmewonder 1

can anyone give me a good definition for agitation in regards to a chemical solution?
please?

2007-05-30 03:30:36 · 5 answers · asked by Kizzzatie 2

2007-05-30 03:19:08 · 1 answers · asked by Remely T 1

1: What is pure Nitrogen obtained from?
It is obtained from ammonium nitrite, NH4NO2
It is obtained from air.
It is obtained from Earth
It is obtained from the Fungus.


2: The brown gas produced when copper reacts witt concentrated nitric acid is
N2O
NO
NO2
N2O3


3: The atomic weight of nitrogen is
14
28
16
36


4: A retort is generally used in preparing
carbonic acid
nitric acid
hypochlorous acid
sulfuric acid


5: The gas obtained when copper unites with dilute nitric acid is
hydrogen
nitric oxide
nitrogen
nitrogen peroxide


6: A gas that is less dense than air is
H2S
NH3
NO2
O2


7: Unstable compounds used as explosives usually con­tain the element
chlorine
nitrogen
phosphorus
sulfur


8: Nitric acid may be prepared by the reaction be­tween
H2SO4 and NaNO3
NaNO3 and KOH
H2S and NH3
H2SO4 and KNO3

2007-05-30 03:18:33 · 2 answers · asked by Anonymous

also include pysical and chemical properties with laboratory test .thank you

2007-05-30 03:11:12 · 1 answers · asked by Ehijie 1

The daily RNI of calcium for adolescent females is 700 to 1100 mg. A supplement table contains 950mg of calcium citrate. Each gram of calcium citrate contains 5.26x10 to the power negative 10 mol calcium. How many tablets would a 16 year old female have to take to meet her daily RNI?

2007-05-30 03:11:12 · 2 answers · asked by John J 1