Chemistry - December 2007

What mass of potassium sulphate would you have to add to a 250 mL volumetric flask to make a solution in which [K+] = 0.100 M

2007-12-06 07:52:51 · 3 answers · asked by Anonymous

2007-12-06 07:37:34 · 10 answers · asked by Anonymous

My partner and i timed how long alieve (the medicine) takes to dissolve in different liquids with different phs, but are project needs relevance and it doesnt make since with reation rate. This project makes since with solubiliy as my teacher told me but I DONT KNOW HOW.!PLEEASE HELP!

2007-12-06 07:13:51 · 4 answers · asked by Anonymous

The following processes occur spontaneously at 25 °C. Which of these processes are endothermic?

1.the combustion of methane to produce water and carbon dioxide
2.the expansion of an ideal gas into a vacuum
3.the melting of ice

a.3 only
b.2 and 3
c.2 only
d.1 and 2

2007-12-06 06:58:26 · 1 answers · asked by Anonymous

Calculate the standard entropy change for the combustion of methanol at 25 °C.

2 CH3OH(λ) + 3 O2(g) → 2 CO2(g) + 4 H2O(g)

Species S° (J/K⋅mol)
CH 3 OH (λ) 127.2
O 2 (g) 205.1
CO 2 (g) 213.7
H 2 O(g) 188.8

a.-312.9 J/K
b.+70.2 J/K
c.+2052.3 J/K
d.-2052.3 J/K
e.+312.9 J/K

2007-12-06 06:50:28 · 1 answers · asked by Anonymous

What colour is dilute ammonium hydroxide in liquid state??

2007-12-06 05:57:08 · 6 answers · asked by JumperXx 1

1. What is Chlorine's origin?

2. What is a common use of Chlorine?

Thanks a Bunch!

2007-12-06 04:56:43 · 2 answers · asked by Anonymous

can you help me out with this question, thanks the help =)

2007-12-06 04:35:11 · 2 answers · asked by Jen 1

a-mole
b-liter
c-kelvin
d-second
e-ampere

2007-12-06 04:31:29 · 5 answers · asked by Anonymous

WHYfree fatty acids are of importance in the context of lipid oxidation

2007-12-06 04:15:42 · 1 answers · asked by mallak s 2

Indicate the repeating unit of the polymer.

2007-12-06 04:11:52 · 2 answers · asked by Anonymous

2007-12-06 04:06:38 · 1 answers · asked by Tanner 1

"Ideal" gas meaning the "Ideal Gas Laws" apply.

2007-12-06 02:43:43 · 6 answers · asked by Jesse R 4

I hav 2 make an ad for uranium what can i use it for bsides killing ppl?

THX

Cammy
~Tennessee Girl~

2007-12-06 02:27:02 · 3 answers · asked by Anonymous

what does INSOLUABLE IN WATER mean?
I am on lots of different meds from my doctor, and this is always stated for "Ativan". what does it mean?
thanks!

2007-12-06 02:26:23 · 6 answers · asked by Anonymous

1.Name each of the following solutions as an acid.
H2Se
HClO2
HClO3
H3PO4
Name each of the following molecules.
SO3
NO
SiF4
NF3

2007-12-06 02:16:31 · 4 answers · asked by Anonymous

A.) Citric acid
B.) Lactate
C.) FAD
D.) Oxaloacetate

2007-12-06 01:55:52 · 4 answers · asked by D.J 1

2007-12-06 01:40:24 · 6 answers · asked by Gator Girl 5

Categorize each of the follwoing as an element compound, mixture, or pure substance
-popsicle
-sugar
-dishwater

If u have a container with hydrogen gas and oxygen gas in it do u have water? why or why not?


give an example of element, compound, a mixture


MUCHO MUCHO MUCHO THANK YOUS
IF U CAN HELP ME =]]

2007-12-06 01:36:21 · 4 answers · asked by Anonymous

what are the chemicals or substances that fermentation tests??

2007-12-06 01:34:34 · 2 answers · asked by khaye 1

A mixture of contain 76.5% NaCl , 6.5% MgCl2 , and 17.0% Na2S04 by mass. What is morality of Cl- ions in a solution formed by dissolving 7.50g of mixture in enough water to form 500.0ml of solution

2007-12-06 01:30:56 · 2 answers · asked by Anonymous

A mixture of gases contains 0.75 mol N2, 0.30 mol O2, and 0.15 mol CO2. If the total pressure of the mixture is 1.56 atm, what is the partial pressure of each component?

2007-12-06 01:16:22 · 4 answers · asked by Anonymous

a. Electrons are either shared or transferred between atoms.
b. Electrons are shared but not transferred between atoms.
c. Electrons are neither shared nor transferred between atoms.
d. Electrons are transferred but not shared between atoms

2007-12-06 01:16:08 · 3 answers · asked by Anonymous

The normal respiratory rate for a human being is 15.0 breaths per minute. The average volume of air for each breath is 505 cm3 at 20degreesC and 9.95 x 10^4 Pa. What is the volumne of air at STP that an individual breathes in one day? Need answer in cubic meters....

2007-12-06 01:05:14 · 1 answers · asked by Anonymous

A sample of oxygen at 40degreesC occupies 820. mL. If this sample later occupies 1250 mL at 60degreesC and 1.40 atm, what was its original pressure?

2007-12-06 01:00:22 · 1 answers · asked by Anonymous

a. Helium does not react with other substances but does form new substances.
b. Helium reacts with other substances but does not form new substances.
c. Helium reacts with other substances to form new substances.
d. Helium does not react with other substances to form new substances

2007-12-06 00:49:54 · 2 answers · asked by Anonymous

A flask containing 155 cm3 of hydrogen was collected unser a pressure of 22.5 kPa. What pressure would have been required for the volumne of gas to have been 90.0 cm3, assuming the same temperature.

2007-12-06 00:45:55 · 2 answers · asked by Anonymous

2007-12-06 00:33:39 · 2 answers · asked by Tanisha K 1

Any reference will help...
thank you...

2007-12-06 00:30:37 · 4 answers · asked by Sawira 2

plz plz plz help!

2007-12-06 00:21:32 · 6 answers · asked by Anonymous