Chemistry - May 2007

2007-05-07 12:09:12 · 4 answers · asked by Keri B 1

I think I know the answer, but am not sure. Thanks for the help.

2007-05-07 10:38:08 · 6 answers · asked by Anonymous

This is about a lab about enzymes which is a potatoe!!

2007-05-07 10:19:21 · 2 answers · asked by ursee 1

This is about a lab about enzymes which is a potatoe!!

2007-05-07 10:18:51 · 2 answers · asked by ursee 1

I'm trying to finish a lab report, and I haven't heard of about 1/2 the words on the lab sheet. In the lab, the equation reads: NaOH (aq) + HCl (ag) --> NaCl (aq) + water

1."Write the net ionic reaction for any neutralization reaction"
-- What is the net ionic reaction?

2."What occurs at the end poing of tritation?"
-- Doesn't the solution reach a pH of 7?

2007-05-07 10:04:58 · 1 answers · asked by orlandoluvr_1990 3

i have to answer these questions, that is the preparation for the big test.
but i was sick and could not attend the lesson. can someone answer the questions and explain them briefly
you will save my life
thanks


Compare a galvanic cell with an electrolysis cell and state in which one (or both?)

a) direct current is consumed
b) direct current is produced
c) reactions occur spontaneously
d) reactions go on when energy is applied
e) an oxidation reaction occurs at one electrode and a reduction at the other

2007-05-07 09:54:08 · 2 answers · asked by Emily 3

TRUE OR FALSE?

2007-05-07 09:37:46 · 6 answers · asked by angelme 1

i have to describe a logical sequence of chemical reactions that would enable me to identify water
i cant use the boiling point or spectra stuff

i was thinking something along the lines of anhydrous copper II sulphate, but i cant remember what happens or the equation or anything

2007-05-07 09:05:53 · 3 answers · asked by ryanbradbury90 1

without any other measurements, I need to know which of the following can be determined; %(w/w), %(w/v), %(v/v)

2007-05-07 08:32:09 · 1 answers · asked by frog 1

What volume (mL) of sulfur dioxide can be produced by the complete reaction of 3.82 g of calcium sulfite with excess HCl (aq), when the final SO2 pressure is 827 torr at 44.0 °C?

2007-05-07 08:22:41 · 3 answers · asked by susan v 1

plz im really nervous cz i have 2 du well!!!!!!!!!!
lol
thanx!!!!!!!

2007-05-07 07:38:56 · 3 answers · asked by Anonymous

a. Most of the volume of an atom is empty space
b. Electrons move around the nucleus as planets orbit the sun
c. Electrons can absorb or emit energy only in whole numbers of photons

d. Atoms have a central positively-charged nucleus

2007-05-07 06:24:36 · 10 answers · asked by HOPING 1

How to determine the formula for polyatomic group such as carbonate ion?

I know that the formula for Carbonate ion is CO3, or that Sulfate ion is SO4. But how do you get there? How to know exactly that Carbon will always go with 3 Oxygens - or that Sulfate will always bond with 4 Oxygens to form sulfate ion?

Are the atomic number and the valence shell the clue to finding out the polyatomic group formula?

Thanks.

2007-05-07 05:46:11 · 2 answers · asked by Forwardium 1

I am in Organic Chemistry Lab and I need to find out what an unknown substance is by Wednesday. It is a yellow powder with a melting point about 144-148 and it contains nitrogen. If anyone could give me an idea what it could be that would be awesome since this lab is 20% of my semester grade.

2007-05-07 05:13:39 · 2 answers · asked by Anonymous

2007-05-07 04:58:26 · 4 answers · asked by Niraj S 1

Both at normal atmopheric pressure and at the negative pressure needed to make it freeze again.Sublimation points must have a significant dwell time difference or is it the same?

2007-05-06 23:54:12 · 1 answers · asked by stratoframe 5

I have to do a servey for my chemistry project.Could you plz help me find the best place for it??

2007-05-06 23:47:24 · 1 answers · asked by K.J. 2

The person who can name as many solvents as they can, get to be best answer and get 10 POINTS!!!!

2007-05-06 23:34:06 · 2 answers · asked by zoe m 1

2007-05-06 23:23:22 · 15 answers · asked by Anonymous

The temp. of the mixture is 48.0°C.

2007-05-06 23:13:47 · 3 answers · asked by Anonymous

2007-05-06 22:24:18 · 6 answers · asked by danny s 1

show working.

2007-05-06 22:18:56 · 4 answers · asked by Anonymous

100 people 365days, whats P(atleast two have birthday on the same day)

2007-05-06 21:50:05 · 4 answers · asked by Anonymous

2007-05-06 21:49:50 · 3 answers · asked by Anonymous

Please help me with this Inorganic Chemistry question!
:)


Use the Valence Shell Electron Pair Repulsion Theory (VSEPR) stating any rules used to predict the shape of the molecular ion, iodine tetrabromide. Draw its structure and comment on any bone angle and bond legth variations you might expect in this molecular ion.


(i couldn't figure out the bonding process, Iodine and 4 x Bromine all have 7 valence electrons?)

2007-05-06 21:41:51 · 3 answers · asked by soshsiao 2

Step 1: A scuba tank is filled to a pressure of about 21,000 kPa at 295K. The volume of the tank is 25 L. Find the number of moles of air in the tank.
Step 2: The molar mass of air is about 29 g. Determine the mass of air in the tank (Use your answer from Step 1 above). If 1 kg = 2.2 lbs, how much does the air weigh?

2007-05-06 21:24:54 · 2 answers · asked by Anonymous

What reactions have been carried out in the wastewater samples in Measurement Of Total Nitrogen

By using :
Sample (after add Nirtra Ver 3 or 6 the color will change to Pink color)
Stock nirite solution
HACH Nirtra Ver6 Nitrate reagent Power Pillows
HACH Nirtra Ver3 Nitrate reagent Power Pillows
Tecator Digestion System
Concentrated Sulphuric Acid
Kjeltabs catalyst

2007-05-06 21:00:15 · 1 answers · asked by wilson96447991 1

2007-05-06 20:30:10 · 2 answers · asked by rosinta s 1

2007-05-06 20:01:56 · 1 answers · asked by Adam L 1

The situation is that right now, at least in my mind, there is a major logical fallacy in my results for a lab experiment, dealing with the supersaturation and crystallization of Sodium Acetate.
For the first step, I poured a certain amount of Sodium Acetate (we used "crystals" as units) into 5 mL of tap water. The result was an increase of temperature (not recorded) and an unsaturated solution.

For the second step, we added a spoonful of Sodium Acetate, resulting in a cooler, saturated solution.

Now, my main question is, why was there an increase in temperature in the first step, yet there was a decrease in temperature in the second step? Does it have something to do with the saturation of the solution?

A response ASAP will be GREATLY appreciated. Thanks.

2007-05-06 19:25:18 · 1 answers · asked by Anonymous