Friday
February 27, 2015

Posts by Lauren


Total # Posts: 1,581

Chemistry
Indicate which is more soluble in ethanol? C2H5OH, acetic acid, CH3COOH, or stearic acid C17H35COOH.
February 4, 2008

Chemistry
People have proposed towing icebergs to arid parts of the earth as a way to deliver freshwater. Explain why icebergs do not contain salts although they are formed by the freezing of ocean water (i.e saltwater)
February 4, 2008

Chemistry
A tank of gas at 21 degrees C has a pressure of 1.0 atm. Using the data in the table answer the following questions. Explain your answers A. If the tank contains carbon tetrafluoride, CF4 is the liquid state also present? B. If the tank contains butane, C4H10 is the liquid ...
February 4, 2008

Chemistry
A quantity of ice at 0.0 degrees C was added to 33.6 of water at 21.0 degree C to give water at 0.0 degrees C. How much ice was added? The heat of fusion of water is 6.01 kJ/mol and the specific heat is 4.18 J/(g * degrees C) q = mass x specific heat x delta T? q = mass x heat...
February 4, 2008

Chemistry
A quantity of ice at 0.0 degrees C was added to 33.6 of water at 21.0 degree C to give water at 0.0 degrees C. How much ice was added? The heat of fusion of water is 6.01 kJ/mol and the specific heat is 4.18 J/(g * degrees C) q = mass x specific heat x delta T? q = mass x heat...
February 4, 2008

Chemistry
Methanol, CH3OH a colorless voltile liquid was formerly known as wood alcohol. It boils at 65 degrees C and has a heat of vaporization of 37.4 kJ/mol. What is its vapor pressure at 22.0 degrees C?
February 4, 2008

algebra
-8+3 = -5 x-5<11 +5 +5 X< 16
February 4, 2008

Chemistry
Snow forms in the upper atmosphere in a cold aid mass that is supersatuated with water vapor. When the snow later falls through a lower, warm air mass, rain forms. When atomic weight is 63.5 amu. Calculate the edge length of the unit cell.
February 4, 2008

Chemistry
On the basis of the description given classify each of the following solids as molecular, metallic, ionic, or covalent network. Explain why? A. a lustrous, yellow solid that conducts electricity B. a hard, black solid melting at 2350 degrees C to give a nonconducting liquid C...
February 4, 2008

Chemistry
well all it asks is name the types of solid it forms and those four our the types of solids. so like LiCl you said it was an ionic compound so it might be ab ionic solid and so on
February 4, 2008

Chemistry
Classify each of the following by the type of solid if forms: a. LiCl b. BaCl2 c. BCl3 d. CCl4 e. NCl3 I have four different types of solids to guess from like Metallic solid, ionic solid, molecular solid, covalent network solid and i dont know which goes with what element
February 4, 2008

Chemistry
Describe the formation of hydrogen bonds in a hydrogen peroxide, H2O2. Represent possible hydrogen bonding structures in hydrogen peroxide by using structural formulas and the conventional notation for a hydrogen bond.
February 3, 2008

Chemistry
Snow forms in the upper atmosphere in a cold aid mass that is supersatuated with water vapor. When the snow later falls through a lower, warm air mass, rain forms. When atomic weight is 63.5 amu. Calculate the edge length of the unit cell.
February 3, 2008

Chemistry
On the basis of the description given classify each of the following solids as molecular, metallic, ionic, or covalent network. Explain why? A. a lustrous, yellow solid that conducts electricity B. a hard, black solid melting at 2350 degrees C to give a nonconducting liquid C...
February 3, 2008

Chemistry
Sorry I clicked to fast but that is the question and I have four different types of solids to guess from Like Metallic solid, ionic solid, molecular solid, covalent network solid and i dont know which goes with what element
February 3, 2008

Chemistry
Which of the following do you expect to be molecular solids? A. sodium hydroxide NaOH B. Solid Ethane C2H6 C. Nickel, Ni D. Solid Silane SiH4
February 3, 2008

Chemistry
I didnt write I cant find it someone else did being stupid and putting my name down as a reply
February 3, 2008

Chemistry
Can't find it.
February 3, 2008

Chemistry
Classify each of the following by the type of solid if forms: a. LiCl b. BaCl2 c. BCl3 d. CCl4 e. NCl3
February 3, 2008

Chemistry
Predict the order of increasing vapor pressure at a given temperature for the following compounds: CH3CH2CH2CH2OH HOCH2CH2CH2OH CH3CH2OCH2CH3
February 2, 2008

Chemistry
which of the following compounds would you expect to exhibit only London forces? CCL4 CCLH CaI2 PCl5
February 2, 2008

Chemistry
A tank of gas at 21 degrees C has a pressure of 1.0 atm. Using the data in the table answer the following questions. Explain your answers A. If the tank contains carbon tetrafluoride, CF4 is the liquid state also present? B. If the tank contains butane, C4H10 is the liquid ...
February 2, 2008

Chemistry
Methanol, CH3OH a colorless, volatile liquid was formely known as wood alcohol. It boils at 65.0 degrees C and has a heat vaporization of 37.4 kJ/mol. What is its vapor pressure at 22.0 degrees C ?
February 1, 2008

Chemistry
A quantity of ice at 0.0 degrees C was added to 33.6 of water at 21.0 degree C to give water at 0.0 degrees C. How much ice was added? The heat of fusion of water is 6.01 kJ/mol and the specific heat is 4.18 J/(g * degrees C)
February 1, 2008

Chemistry
Liquid Butane, C4H10, is stored in cylinders to be used as a fuel. Suppose 39.3g of butane gas is removed from a cylinder. How much heat must be provided to vaporize this much gas? The heat of vaporization of butane is 21.3 kJ/mol.
January 31, 2008

Chemistry
Liquid Butane, C4H10, is stored in cylinders to be used as a fuel. Suppose 39.3g of butane gas is removed from a cylinder. How much heat must be provided to vaporize this much gas? The heat of vaporization of butane is 21.3 kJ/mol.
January 31, 2008

Chemistry
A 35.8f sample of cadminum metal was melted by an electric heater 4.66 J/s of heat. If it took 6.92 min from the time the metal began to melt until it was completely melted, what is the heat of fusion per mole of cadminum?
January 31, 2008

Business
In a world without trade, what would American consumers have to pay for logitech's products?
January 24, 2008

Chemistry
Phase diagrams- Explain how the density of the solid and liquid phase would compare.
January 16, 2008

Chemistry
I think this might be right...adjusting the volume for temperature. 273K + 23K= 296K The two possible temperature ratio would be 296K/273K or 273K/296K. I chose the second one. 57.6 ml(273K)/296K answer: 53.1 ml
January 16, 2008

Chemistry
A eudiometer contains 65.0 ml sample of gas collected by the diplacement of water. The water levels inside and outside the eudiometer are the same. The atmospheric pressure is 92.5 kPa and the temperture is 23 degrees. What volume will the dry gas occupy at STP? The vapor ...
January 16, 2008

Chemistry
A pocket of gas is discovered in a deep drilling operation. The gas has a temperature of 480c and is at a pressure of 12.8 atm. What volume of gas is required to provide 18.0 L of gas at the surface where the conditions are 22 C and 1.00 atm?
January 15, 2008

Chemistry
Answer check: Define a catalyst and explain a catalyst's role in a chemical reaction. A catalyst is a substance that speeds a chemical reaction without being permanently changed itself. It works by providing a convenient surface for the reaction to occur. The reacting ...
January 14, 2008

English
Hi, I need to know the background on the literay term: interjection. I have the definition and examples of it, but I can't seem to find any history on it. Help would be appreciated. Thank you so much!
December 16, 2007

Chemistry
Which if the following compounds is insoluble in water (NH4)2CO3 AgBr CuSO4 KI LiNO3 is it CuSO4 because sulfates are insolube
December 12, 2007

Chemistry
to lead nitrate because it is solube
December 12, 2007

Chemistry
a precipitate is expected when an aqueous solution of potassium iodide is added to an aqueous solution of: sodium sulfate iron(II) chloride calcium perchlorate barium hydroxide lead nitrate
December 12, 2007

Science
Explain Why A Hot Air Balloon Rises
December 12, 2007

Chemistry
Which if the following compounds is insoluble in water (NH4)2CO3 AgBr CuSO4 KI LiNO3 I thought it might be AgBr
December 11, 2007

Chemistry
When an aqueous solution of lithium chloride is mixed with an aqueous solution of ammonium sulfate a precipitate forms a new salt is formed a gas is evolved an acid and base are formed no reaction occurs I either thought it was a precipitate forms or no reaction occurs
December 11, 2007

Chemistry
All of the following are weak acids except HF H3PO4 H2SO4 HNO2 HC2H3O2
December 11, 2007

Chemistry
Which of the following is a weak base HOCl LiOH Ba(OH)2 KOH NH3
December 11, 2007

Chemistry
Which of the following indicates the exsistence of stron intermolecular forces of attraction in a liquid? a very low boiling point a very low vapor pressure a very low critical pressure a very low viscosity a very low heat of vaporization
December 11, 2007

Chemistry
Which of the following molecules has polar bonds and is nonpolar? HF ICI3 NF3 SF4 BF3
December 11, 2007

Chemistry
How do you make CIF2 into a Lewis Structure
December 5, 2007

Chemistry
Can you tell me if i did these right?? Lewis Dot Structure A. BrF = 5 dots around Br-F with 5 dots around it B. PBr3 = ? I dont know how to do because of the 3 C. NOF= 3 dots around N 2 dots around O and 5 dots around F N-O-F D. CO = 3 dots around C double bond between O and 4...
December 3, 2007

Chemistry
i dont know what the resonance description is so i dont have anything yet
December 3, 2007

Chemistry
write the resonance desription for the following A. ClNO2 B. NO-2
December 3, 2007

Chemistry
Decide which of the following bonds is least polar on the basis of electronegativities of atoms, H---S, Si---Cl, N---Cl.
November 30, 2007

Chemistry
nevermind i got it
November 30, 2007

Chemistry
Use Lewis Symbols to show the reaction of atoms to form arsine, AsH3. Indicate bonding pairs in the Lewis formula of AsH3 are bonding and which are lone pairs.
November 30, 2007

Math
How do I do a tree diagram to find the least common multiple
November 28, 2007

Chemistry
The principal quantum number of the valence electrons in an atom of lead is: A. 2 B. 3 C. 4 D. 5 E. 6
November 19, 2007

Chemistry
Which of the following elements has the smallest ionization energy? A. F B. Be C. B D. Mg E. C
November 19, 2007

Chemistry
How many valence electrons does phosphourous have
November 18, 2007

Chemistry
The maximum number of electrons that can be accomodated in a p subshell is A.2 B.4 C.6 D. 8 E. 10
November 18, 2007

Chemistry
The principal quantum number of the valence electrons in a atom of lead is A. 2 B. 3 C. 4 D. 5 E. 6
November 18, 2007

Chemistry
All of the following are true EXCEPT; A. the n=4 energy level has no f orbitals B. the 2p orbitals can have a maximum if 6 electrons C. the s orbital has a spherical shape D. there are 5 orbitals in a set E. the n=3 energy level has a set of d orbitals.
November 18, 2007

physics
6.4 m/s
November 11, 2007

Chemistry
so I did 1 divided by 4797297.498 and got 2.085 X 10^-7
November 4, 2007

Chemistry
so i got 1/4797297.498
November 4, 2007

Chemistry
okay so it should look like this 1/lambda= 1.0967758341 x 10^7(3^2)*[(1/3^2)-(1/4^2)] 1.0967758341 x 10^7(9)(.0486) i got 4798394.274
November 4, 2007

Chemistry
What is the wavelength of the transition from n=4 to n=3 for Li2+? In what region of the spectrum does this emission occur? Li2+ is a hydrogen-like ion. Such an ion has a nucleus of charge +Ze and a single electron outside this nucleus. The energy levels of the ion are -Z^2RH/...
November 4, 2007

Chemistry
Help needed for writing up a balance chemical equation for an acid/base titration: for an extended experimental experiment we tested the total acid content of orange juice, then had to write the balanced chemical equation for the experiment to do further calculations but i am ...
November 3, 2007

Chem
so am I solving for Rh This is what the equation should look like right: 1/9= Rh (1/2)-(1/3)
November 3, 2007

Chem
What is the wavelength of the transition from n=4 to n=3 for Li2+? In what region of the spectrum does this emission occur? Li2+ is a hydrogen-like ion. Such an ion has a nucleus of charge +Ze and a single electron outside this nucleus. The energy levels of the ion are -Z^2RH/...
November 3, 2007

Chemistry
What is the wavelength of the transition from n=4 to n=3 for Li2+? In what region of the spectrum does this emission occur? Li2+ is a hydrogen-like ion. Such an ion has a nucleus of charge +Ze and a single electron outside this nucleus. The energy levels of the ion are -Z^2RH/...
November 3, 2007

Chem
Thank you
November 3, 2007

Chem
well 9.98 X 10^11 / 3.00 x 10^8 = 3326.66
November 3, 2007

Chem
yes as you can see i put them in the answer i just dint type them out
November 3, 2007

Chem
9.98 X 10^11m = 3.00 X 10^8m/s (time) so I converted 998 million km into m now I divided 9.98/ 3.00 and got 3.33 x 10^19 is this correct
November 3, 2007

Chem
So rate is the speed of light too
November 3, 2007

Chem
The space probe Pioneer 11 was launched April 5,1973, and reached Jupiter in December 1974 traveling a distance of 998 million km. How long did it take an electromagnectic signal to travel to earth from Pioneer 11 when it was near Jupiter. The speed of light is, for all ...
November 3, 2007

Chemistry
so that website means that i need to use 1.6726 x 10^-27 kg why that number
November 3, 2007

Chemistry
What is the wavelength of a proton traveling at a speed of 6.21 km/s? What would be the region of the spectrum for electromagnetic radiation of this wavelength. For this one I did the same thing 6.63 X 10^-34/ (? kg)(6210 m/s) = How do get the kg for the problem
November 3, 2007

Chemistry
6.63 X 10^-34/ (2.66X 10^-26 kg)(521 m/s) = 1.30 X 10^-5 is this correct
November 3, 2007

Chemistry
so I dont need to go any father I just plug this back into the original problem and get my answer right
November 3, 2007

Chemistry
2.66 X 10 ^-23 (0.001 kg/1 g) = 2.66X 10^-26 that is what I want is kg
November 3, 2007

Chemistry
so that equals 2.66 grams/ 1 atom now where do I go from there
November 3, 2007

Chemistry
yes I know how big that is but I figured that you had 2 atoms of 6.02 x 10^23 so I divided by 2 to get the mass of 1 mol which is 3.01 X 10^23... why wouldnt you just take the 100 pm and make it into kg.
November 3, 2007

Chemistry
3.01 x 10^23 ???
November 3, 2007

Chemistry
sorry I copied the wrong problem it is supposed to be: 521 m/s not 6210 m/s 6.63 X 10^-34/ (? kg)(521 m/s) How do I get the kg for this problem
November 3, 2007

Chemistry
What is the de Broglie wavelength of an oxygen molecule, O2 traveling at 521 m/s? Is the wavelength much smaller or much larger than the diameter of an atom. (on the order of 100 pm) De Broglie wavelength = h/mv h = Planck's constant in J*s. m is mass in kg. v is velocity ...
November 3, 2007

Chemistry
The space probe Pioneer 11 was launched April 5,1973, and reached Jupiter in December 1974 traveling a distance of 998 million km. How long did it take an electromagnectic signal to travel to earth from Pioneer 11 when it was near Jupiter. Where do I begin???
November 1, 2007

Chemistry
What is the de Broglie wavelength of an oxygen molecule, O2 traveling at 521 m/s? Is the wavelength much smaller or much larger than the diameter of an atom. (on the order of 100 pm) How do I do this
November 1, 2007

Chemistry
What is the wavelength of a proton traveling at a speed of 6.21 km/s? What would be the region of the spectrum for electromagnetic radiation of this wavelength. How do I do this
November 1, 2007

Chem
How much heat is released when a mixture containing 10.0g CS2 and 10.0 g Cl2 reacts by the equation. CS2 + 3Cl2 ----> S2Cl2 + CCl4 Delta H = -230 kJ
November 1, 2007

Chemistry
A sample of natural gas is 80.0% CH4 and 20.0% C2H6 by mass. What is the heat from the combustion of 1.00 g of this mixture? Assume the products are CO2 and H2O. CH4 = -74.87 and C2H6 = -84.68
November 1, 2007

Chem
is 3.00 x 10^8 m/s the speed of light
November 1, 2007

Chem
distance is 998 million km what is veloctyoflight
November 1, 2007

Chem
The space probe Pioneer 11 was launched April 5,1973, and reached Jupiter in December 1974 traveling a distance of 998 million km. How long did it take an electromagnectic signal to travel to earth from Pioneer 11 when it was near Jupiter.
November 1, 2007

Chem
frequency = speed of light/656 nm how do you find the speed of light
November 1, 2007

Chem
Calculate the frequency associated with light of wavelength 656nm. (this corresponds to one of the wavelengths of light emitted by the hydrogen atom.)
November 1, 2007

Chem
Microwaves have frequencies in the range 10^9to 10^12/s (cycles per second) equivalent to between 1 gigahertz and 1 terahertz. What is the wave length of microwave radiation whose frequency is 1.258 X 10^10/s? How do I solve this problem
November 1, 2007

Chemistry
what do you mean by proportions???
November 1, 2007

Chemistry
How much heat is released when a mixture containing 10.0g CS2 and 10.0 g Cl2 reacts by the equation. CS2 + 3Cl2 ----> S2Cl2 + CCl4 Delta H = -230 kJ
November 1, 2007

Chemistry
so CH4 = -74.87 and C2H6 = -84.68 what do you mean by take 80% and 20%???
November 1, 2007

Chemistry
A sample of natural gas is 80.0% CH4 and 20.0% C2H6 by mass. What is the heat from the combustion of 1.00 g of this mixture? Assume the products are CO2 and H2O. How do I do this
November 1, 2007

Chemistry
sorry it is supposed to say When 23.6 of calcium chloirde CaCl2 was dissolved in water in a calorimeter, the temperature rose from 25.0 degrees C to 38.7 degrees C. If the heat capacity of the solution and the calorimeter is 1258 J/ degrees C, what is the enthalpy change when ...
November 1, 2007

Chemistry
When 23.6 of calcium chloirde CaCl2 was dissolved in water in a calorimeter, the temperature rose from 25.0 degrees C to 21.56 degrees C. If the heat capacity of the solution and the calorimeter is 1071 J/ degrees C, what is the enthalpy change when 1 mol of sodium nitrate ...
November 1, 2007

Pages: <<Prev | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | Next>>

Members