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October 25, 2014

Posts by Lauren


Total # Posts: 1,532

Physics
At time t = 0s, a puck is sliding on a horizontal table with a velocity 3.00 m/s, 65.0 above the +x axis. As the puck slides, a constant acceleration acts on it that was the following components: ax = 0.460m/s2 and ay = 0.980m/s2. what is the velocity of the puck at time t = 1...
February 14, 2008

Chemistry
is it 60 g of urea for the molar mass annd then take the 0.00457/60 and get grams ???
February 11, 2008

Chemistry
Urea (NH2)2CO is dissolved in 100.0 g of water. The solution freezes at -0.085 degrees C. how many grams of urea were dissolved to make this solution. delta T = Kf*molality Plug in 0.085 for delta T, I assume you know Kf for water, calculate molality. Then molality x kg ...
February 11, 2008

Chemistry
Aluminum hydroxide forms a positively charged sol. Which of the following ionic substances should be most effective in coagulating the sol? NaCl CaCl2 Fe2(SO4)3 K3PO4 The idea behind coagulating sols is to use those salts that have the highest + and - charges and the most ions...
February 11, 2008

Chemistry
so they are the same and both dissolve in ethanol or acetic acid dissolves in ethanol because they are small molecules
February 11, 2008

Chemistry
Indicate which is more soluble in ethonal: acetic acid CH3COOH or stearic acid C17H35COOH I think acetic acid maybe more soluble but I dont know why
February 11, 2008

Chemisty
Aluminum hydroxide forms a positively charged sol. Which of the following ionic substances should be most effective in coagulating the sol? NaCl CaCl2 Fe2(SO4)3 K3PO4 The idea behind coagulating sols is to use those salts that have the highest + and - charges and the most ions...
February 11, 2008

Chemisty
Aluminum hydroxide forms a positively charged sol. Which of the following ionic substances should be most effective in coagulating the sol? NaCl CaCl2 Fe2(SO4)3 K3PO4
February 9, 2008

Chemistry
A solution contains 0.0653g of compound in 8.31g of ethanol. The molarity of the solution is 0.0368m. Calculate the molecular weight of the compound For Further Reading Chemisty - drbob222, Thursday, February 7, 2008 at 9:40pm The molarity of the solution can't be 0.0368 m...
February 9, 2008

Chemistry
so it would be 0.085 degrees C = 1.86 C/m (0.1 kg/60 g of (NH2)2CO
February 9, 2008

Chemistry
wait no its 1.858 Kf(degress C/m)
February 9, 2008

Chemistry
Urea (NH2)2CO is dissolved in 100.0 g of water. The solution freezes at -0.085 degrees C. how many grams of urea were dissolved to make this solution. delta T = Kf*molality Plug in 0.085 for delta T, I assume you know Kf for water, calculate molality. Then molality x kg ...
February 9, 2008

Chemistry
well actually i double clicked the submit button and it posted it twice... sorry
February 9, 2008

Chemistry
Urea (NH2)2CO is dissolved in 100.0 g of water. The solution freezes at -0.085 degrees C. how many grams of urea were dissolved to make this solution. delta T = Kf*molality Plug in 0.085 for delta T, I assume you know Kf for water, calculate molality. Then molality x kg ...
February 9, 2008

Chem
well you have more 00.00 sig figs than 3 so i would put it as 4 sig figs not 3
February 8, 2008

Math
38 x 7 = 266
February 8, 2008

Chemisty
sorry my fault it is suppose to be molality
February 7, 2008

Chemisty
A solution contains 0.0653g of compound in 8.31g of ethanol. The molarity of the solution is 0.0368m. Calculate the molecular weight of the compound
February 7, 2008

Chemistry
Urea (NH2)2CO is dissolved in 100.0 g of water. The solution freezes at -0.085 degrees C. how many grams of urea were dissolved to make this solution.
February 7, 2008

Chemistry
A solution was prepared by dissolving 0.817g of sulfur S8, in 100.0g of acetic acid, HC2H3O2. Calculate the freezing point and boiling point of the solution
February 7, 2008

Chemistry
92.40 [mmHg]
February 7, 2008

Chemistry
What is the vapor pressure at 23 degree C of a solution of 1.20g of naphthalene, C10H8 in 25.6 g of benzene, C6H6? The vapor pressure of naphthalene can be neglected. Calculate the vapor-pressure lowering the solution
February 7, 2008

Chemistry
Citric acid H3C6H5O7, occurs in plants. Lemons contain 5% to 8% citric acid by mass. The acid is added to beverages and candy. An aqueous solution is 0.688m citric acid. The density is 1.049 g/ml. What is the molar concentration?
February 7, 2008

Chemistry
Citric acid H3C6H5O7, occurs in plants. Lemons contain 5% to 8% citric acid by mass. The acid is added to beverages and candy. An aqueous solution is 0.688m citric acid. The density is 1.049 g/ml. What is the molar concentration?
February 7, 2008

Chemistry
Concentrated aqueous ammonia contains 1.00 mol NH3 dissolved in 2.44 mol H20. What is the mole fraction of NH3 in concentrated aqueous ammonia? What is the molal concentration of NH3
February 7, 2008

algebra
i think its 216
February 7, 2008

algebra
alright thanks anyway
February 7, 2008

algebra
but then the directions say variable substitution
February 7, 2008

algebra
so is that it?? simple as that?
February 7, 2008

algebra
so then its x^2-6 =0 and ^2-3=0 and the dont i put the root sign over the x^2 to get rid of the x^2? and then i end up with x + or - the suare root of 6 = 0 or is that wrong??
February 7, 2008

algebra
is it (x^2 - 6) (x^2 - 3) ??
February 7, 2008

algebra
use variable substitution and factoring to find all of the roots of each equation. x^4-9x^2+18=0 how do you do this??
February 7, 2008

Chemistry
ok i know how to figure out the 2nd equation 45.0g CHCl3(1 mols/118gCHCl3)=.381 mols CHCl3 but how do you get molarity. with kg solvent
February 6, 2008

Chemistry
Caffeine C8H10N4O2, is a stimulant found in a tea and coffee. A sample of the substance was dissolved in 45.0g of choloroform CHCl3 to give a 0.0946m solution. How many grams of caffine were in the sample. m = molality
February 6, 2008

Chemistry
29.575/455*100=6.5% Yay :)
February 6, 2008

Chemistry
so then i did it wrong... :( is it 142g for the Na2SO4 that needs to be put into there
February 6, 2008

Chemistry
How would you prepare 455 g of aqueous solution that is 6.50% sodium sulfate Na2SO4 by mass? percent by mass = grams/100 g solution. X grams/455 = 0.065 solve for X. Subtract 455-X to calculate how much water must be added. ok i got -454.935 is this right
February 6, 2008

Chemistry
23.0769 right
February 6, 2008

Chemistry
so for this part (g Na2SO4/g solution) = (1.50 g Na2SO4/x g solution). it would be (g Na2SO4/ .065 g solution = 1.50 g Na2SO4/ x .065 g solution ) or did i miss place them
February 6, 2008

Chemistry
What mass of solution containing 6.50% sodium sulfate N2SO4 by mass contains 1.50g Na2SO4 Set up a proportion. (g Na2SO4/g solution) = (1.50 g Na2SO4/x g solution). Solve for x. Check my work. how do you fine g solution
February 6, 2008

Chemistry
Determine the mass of the element. What element is it? what is the molar volume of the metal in cubic centimeters(avogadro's number should be used for this problem -1cm=10^7 nm)
February 6, 2008

Chemistry
What is the molar volume of the metal in cubic centimeters? (Avogadro's number should be used for this problem ------ 1 cm = 10^7 nm what is the molar volume of the metal in cubic centimeters(avogadro's number should be used for this problem -1cm=10^7 nm)
February 6, 2008

Chemistry
The question is what is the volume of the unit cell? I dont understand how to get the volume of it
February 6, 2008

Chemistry
what is the volume of the unit cell? A metal crystallizes in a face-centered cubic lattice. The radius of the atom is 0.197 nm. The density of the element is 1.54 g/cm^3
February 6, 2008

Chemistry
NaCl crystallizes in face-centered cubic cell. what is the total number of ions(Na+ ions and Cr- ions) that lie withing a unit cell of NaCl? 2 4 8 6 5
February 6, 2008

Chemistry
What portion of the volume of each atom or ion on the face of a unit cell is actually within the unit cell 1/2 1/4 3/4 all of it none of it
February 6, 2008

Chemistry
The unit cell with all sides the same length and all angles equal to 90 degrees that has lattice points only at the corners is called monoclinic body-centered cubic primative cubic face-centered cubic spherical cubic
February 6, 2008

Chemistry
Determine the mass of the element? what element is it? Ca Ag Ti Mg Al
February 6, 2008

Chemistry
what is the molar volume of the metal in cubic centimeters(avogadro's number should be used for this problem -1cm=10^7 nm)
February 6, 2008

Chemistry
what is the volume of the unit cell
February 6, 2008

Chemistry
What mass of solution containing 6.50% sodium sulfate N2SO4 by mass contains 1.50g Na2SO4
February 4, 2008

Chemistry
How would you prepare 455 g of aqueous solution that is 6.50% sodium sulfate Na2SO4 by mass?
February 4, 2008

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

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