Chemistry - March 2007

a) 0.100 L of 0.250 M NH3 + 0.050 L of 0.250 M HCl


b) 0.100 L of 0.250 M NH4Cl + 0.050 L of 0.025 M HCl


c) 0.100 L of 0.250 M NH4Cl + 0.050 L of 0.250 M NaOH


d) 0.100 L of 0.250 M NH4Cl + 0.150 L of 0.250 M NaOH

2007-03-16 06:26:30 · 1 answers · asked by simonkf2002 1

0.220 M HC3H5O2 ( use Ka = 1.30 x 10 -5 ) and 0.220 M NaC3H5O2 .

2007-03-16 06:25:20 · 2 answers · asked by simonkf2002 1

2007-03-16 06:22:51 · 3 answers · asked by Anonymous

Help me solve this problem!
The molecular formula of a hydrocarbon is to be determined by analyzing its combustion products and investigating its colligative properties.
1) The hydrocarbon burns completely, producing 7.2 grams of water and 7.2 liters of CO2 at standard conditions. Calculate the empiracle formula of teh hydrocarbon.
2) Calculate the mass in grams of O2 required for the complete combustion of the sample of the hydrocarbon described in part 1.
3) The hydrocarbon dissolves readily in CHCl3. The freezing point of a solution prepared by mixing 100 grams of CHCl3 and .600 gram of the hydrocarbon is -64.0 degrees celcius. The molar freezing point depression constant of CHCl3 is 4.68 degrees celcius per molal and its normal freezing point is -63.5 degrees celcius. Calculate the molecular weight of the hydrocarbon.
4) What is the molecular formula of the hydrocarbon?

2007-03-16 06:17:15 · 4 answers · asked by Anonymous

Trisodium phosphate (Na3PO4) is available in hardware stores as TSP and is used as a cleaning agent. The label on a box of TSP warns that the substance is very basic (caustic or alkaline). What is the pH of a solution containing 99.9 g of TSP in a liter of solution?


Can someone walk me through this problem?

2007-03-16 06:16:42 · 2 answers · asked by protege moi 3

2007-03-16 06:14:03 · 3 answers · asked by ladona c 1

2007-03-16 06:04:43 · 5 answers · asked by Anonymous

CAN ANY ONE TELL ME WHICH IS THE POISONOUS CHEMICAL.

2007-03-16 05:58:30 · 3 answers · asked by powerx 1

1: Catalytic "cracking' is a process used to manufacture
acetic acid
explosives
gasoline
soap
WRONGWRONGCORRECTWRONG


2: Natural gas is chiefly
carbon monoxide
ethane
hydrogen
methane
WRONGWRONGWRONGCORRECT


3: Water gas consists principally of a mixture of hydrogen and
carbon monoxide
nitrogen
oxygen
steam
CORRECTWRONGWRONGWRONG


4: The reagents for the preparation of water gas may be
coke and carbon dioxide
coke and steam
scrap iron and air
scrap iron and steam
WRONGCORRECTWRONGWRONG


5: Using high temperature and pressures to split petroleum molecules is called
cracking
destructive distillation
fission
fractional distillation
WRONGWRONGWRONGCORRECT


6: The chief impurity in producer gas is
CH
CO
CO2
N2
WRONGCORRECTWRONGWRONG


7: A pipeline originating in Texas furnishes some sections of New York state with
acetylene
coal gas
natural gas
producer gas
WRONGWRONGCORRECTWRONG


8: Water gas may be produced by the action of steam on hot
calcium
carbon
iron
sodium
WRONGCORRECTWRONGWRONG


9: The process of increasing the amount of gasoline obtained from petroleum is called
cracking
catalysis
fractional distillation
destructive distillation
CORRECTWRONGWRONGWRONG


10: The principal solid fuels used in industry are
wood and coal
coal and coke
charcoal and coke
wood and coke
WRONGCORRECTWRONGWRONG


11: A low-grade gaseous fuel not used in homes because it is poisonous is
producer gas
water gas
coal gas
natural gas
CORRECTWRONGWRONGWRONG


12: The destructive distillation of soft coal yields as one of its products the gaseous fuel
water gas
methane
coal gas
hydrogen
WRONGWRONGCORRECTWRONG


13: The gaseous fuel that furnishes more heat than the other fuel gases is
water gas
acetylene
natural gas
producer gas
WRONGWRONGCORRECTWRONG


14: The liquid remains of plants and animals compose
acetylene
petroleum
alcohol
water gas
WRONGCORRECTWRONGWRONG


15: The process by which simple gaseous hydrocarbons are combined into a liquid hydrocarbon is
cracking
distillation
hydrogenation
polymerization

2007-03-16 05:51:51 · 2 answers · asked by Anonymous

Calculate the molar solublity of Ca(IO3)2 in 0.305 M Ca(NO3)2.
(Ksp = 7.1×10-7 for Ca(IO3)2.)

I tried a bunch of different methods. I though it was the ksp/M^2 but the answer is wrong...Help please

2007-03-16 05:45:35 · 2 answers · asked by Anonymous

By rocket fuel i don't mean toy or model rockets, i mean actual rocket fuel, i hear that hydrogen peroxide could be used as a rocket fuel but is there any other types of fuels i should know about?

2007-03-16 05:30:37 · 7 answers · asked by Anonymous

8: As carbon chains to itself to form long structures, it most often undergoes a(n) ______ bond.
Ionic
Covalent
Nuclear
James


9: Amino acids chain together to form the next order of structure known as the:
Polypeptide
Protein
Nucleic acid
Enzyme


10: On earth, Carbon exists mostly as a(n) _______ quantity.
Mobile
Scarce
Stored
Undesired

2007-03-16 05:22:35 · 5 answers · asked by Anonymous

Can somebody help me solve this multi-step chemistry problem? We learned about them at the beginning of the year and I completely forgot the rules and stuff. Thanks!

3. Use simple structure and bonding models to account for each of the following:
(a) The bond length between two carbon atoms is shorter in C2H4 than in C2H6.
(b) The H-N-H bond angle is 107.5 degrees in NH3.
(c) The bond lengths in SO3 are all identical and are shorter than a sulfur-oxygen single bond.
(d) The I3 - ion is linear.

2007-03-16 05:21:11 · 2 answers · asked by Prue 3

1: Through the carbon cycle, carbon is exchanged between the ________ of the earth.
Water
Land
Air
All of these



2: The main reason that carbon is so versatile and important to life is due to:
It’s name
Carbon’s bonding ability
Carbon’s high electronegativity
None of these


3: Which of the following are not carbon compounds?
Diamond
Bukminster Fullerene
Pyrite
Graphite



4: The distinguishing feature of the aromatic hydrocarbon is it’s ______ structure.
Linear
Soccer ball
Ring
Cone like



5: Hydrocarbons with double bonds are generally considered:
Alkanes
Alkynes
Alkenes
Aromatics



6: The fundamental building blocks of proteins are:
Enzymes
Polypeptides
Nucleic acids
Amino acids




7: The carbon compounds best know as catalysts that fit other compounds like puzzle pieces are:
Enzymes
Polypeptides
Nucleic Acids
Amino Acids

2007-03-16 05:20:53 · 4 answers · asked by Anonymous

Is this a common ion effect? Can we add that H+ produced when substituting its concentration in pH equation?

2007-03-16 05:19:22 · 2 answers · asked by cloudy 1

2007-03-16 05:08:43 · 3 answers · asked by Atticus 1

2007-03-16 05:00:06 · 3 answers · asked by sky_blue 1

These are a few problems I have. Please just tell me what law to use and what number is what. Thanks!

1. A stainless steel tank has a volume of 25 L. When the tank held 15.4 moles of helium, the pressure of the gas was 755 torr. The tank developed a small leak and lost 4.2 moles of gas. If the temperature remained unchanged, what was the pressure in the tank after the loss?

2. What is the volume of H2 gas requred to produce 7.53 liters of ammonia gas (NH3) at STP?
N2 + 3H2 --> 2NH3

3. The pessure of the air in an automobile tire was 32 lbs/in^2 when the tire was cool (20 degrees Celsius). After being driven for a while, the tire pressure was 38 lbs/in^2 . If the volume of the tire stays constant and no leaks develop, what is temperature of the air in the tire after driving?

4. 138 grams of Carbon Disulfide (CS2) vapors at STP were allowed to expand into an empty 50.0 L tank. After being moved to a location in the sun, the pressure was 1.14 atm. What is the temperature?

2007-03-16 04:35:02 · 3 answers · asked by Anonymous

calculate the standard enthalpy change for the reaction of combustion of 1 mole of glucose, C6H1206(s), to carbon dioxide gas and gaseous water.

2007-03-16 04:14:38 · 1 answers · asked by vntraderus88 1

2007-03-16 03:59:35 · 1 answers · asked by jeya k 1

A certain volume of oxygen at an initial pressure of 101.3 kPa is compressed to four-fifths of its original volume. What is the new pressure?

Sorry i have no idea how to figure this out because I dont know what equation to use. Thanks.

2007-03-16 03:58:18 · 6 answers · asked by Anonymous

2007-03-16 03:12:40 · 4 answers · asked by kohlirosy 1

2007-03-16 03:09:36 · 1 answers · asked by james 1

I am a soap maker who uses sodium hydroxide as part of the soap making process. I recently ordered a small plastic container of sodium hydroxide. When it arrived and I tried to use it (pour it out of the original container) the granules flew out of the bottle in all directions. Is there some way to de activate this charge as this product is dangerous to work with already without having it flying out at me in all directions.

Thanks for any help or suggestions.

2007-03-16 03:07:55 · 3 answers · asked by jmmil2011 1

2007-03-16 03:07:41 · 15 answers · asked by Anonymous

2007-03-16 02:33:59 · 9 answers · asked by wtfroflwafl 1

2007-03-16 02:21:50 · 2 answers · asked by lilballerina2004 1

HCOOH (aq).Use KA 1.8X10

2007-03-16 02:17:50 · 1 answers · asked by tikki 2

Analysis of compound "X" (molar mass 72) containing C, H, and O gave and analysis of 66.7% C and 11.1% H. the compund neither reacted with pheny hydrozine nor gave a positive iodoform test (that's the HALOFORM test). reaction with OZONE and subsequent hydolysis gave METHANAL as on of the products. A mole of "X" absorbed a mole of hydrogen when catalytically hydrogenated to give a product "Y" which could be oxidzed by KMNO4 (pottasium permanganate) to a product "Z" (molar mass 72) which did not react with Fehling's solution. Identify the compounds X, Y and Z.

so far i have found the molecular formula of the compound to be C8H8O. and the degree of unsaturation to be 1. i wanted to really know what is the structure of this compound.

i thought it would be .......CH2=CHCH2CH3
.....................................................|.....................................................
....................................................OH.............................................

2007-03-16 02:10:55 · 2 answers · asked by CaribbeanChica 3

When 5.00g of NaOH(s) are added to 100g of water at 25.1 C in a calorimeter also at 25.1 C, the temperature rises from 25.0 to 37.5 C. calculate the molar heat of solution,
NaOH(s)--->Na(aq)+OH(aq). Assume specific heat capacity of water is 4.18J/gK and that of the NaOH(aq) solution is the same.

2007-03-16 01:53:58 · 1 answers · asked by nik 1