Wednesday

September 2, 2015
Number of results: 60,666

**UNE**

How many grams of sodium carbonate is required to have a complete reaction with 1.00g of calcium chloride dihydrate? I can't figure this out...help!
*October 17, 2009 by Erin*

**College Chemistry**

Are my calculations correct of i came up with 50.71g of CaH2 to the question, "How many grams of are needed to generate 54.5 of gas if the pressure of is 815 at 22?"
*November 7, 2009 by Jena *

**compose**

if 3.85 L of carbon monoxide was collected over water at 25 degrees celsius and 689 mmHg how many grams of formic acid were consumed?
*December 8, 2009 by j*

**Chemistry**

How many grams of carbon dioxide are produced if you react 200g of benzaldehyde reacr with 32g of oxygen? its stoichiometry, i have no idea how to do this...
*January 12, 2010 by Jason*

**Chemistry**

how would I find the mass of something from the molality..... How many grams of water should be added to 25.0 g of NaCl to produce a 0.450 m solution?
*February 10, 2010 by CC*

**Chemistry**

Calculate the grams of solute required to make the following solutions. a)2500g of saline solution (0.90% NaCl (m/m)) b)0.050kg of 4.0% (m/m) MgCl2
*April 27, 2010 by Kim*

**chemistry**

How much energy would be needed to vaporize 150 grams of ethanol when it is at its boiling point? Hear of Vaporization (kj/kg)...841.00
*May 23, 2010 by Julia*

**chemistry**

What mass of water (in grams) is needed to dissolve 28.7 g of ammonium nitrate NH4NO3 in order to prepare a 0.452 m (molal) solution?
*September 8, 2010 by Diana*

**CHEMISTRY..please help..thanks**

A laboratory assistant needs to prepare 325 mL of 0.110 M CaCl2 solution. How many grams of calcium chloride will she need?
*November 9, 2010 by Jasmin*

**Math**

Write the Unit Rate as a fraction? 13 grams per cubic centermeters... there are other problems like this but i just need to know how to do this.
*December 12, 2010 by Ansar*

**Chemistry**

Determine the number of grams of water which are required to dissolve a mixture of 25 g of KNO3 and 2.0 g of CuSo4 * 5H20 AT 100 Degrees celscius?
*February 9, 2011 by Jessica*

**Chemistry**

How many grams of water vapor (H2O) are in a 10.2 liter sample at 0.98 atmospheres and 26°C? Show all work used to solve this problem.
*March 19, 2011 by Victoria Ann*

**Chem**

10 grams of sodium chloride is treated with excess silver nitrate AgNO3 + NaCl =AgCl +NaNO3.. HOW MUCH IS PERCIPITATED
*July 4, 2011 by Jessica *

**chemistry**

What is the maximum amount of ethanol (in grams) that can be produced when 0.30 kg of ethylene (C2H4) and 0.029 kg of steam are placed into the reaction vessel?
*September 22, 2011 by Anonymous*

**science**

a can potatoes has the following data: recall 4-9system carbs=22 fat is 10 grams and protien is 13 find the percentage of each if the calories = 275
*October 4, 2011 by paul*

**Physical Science**

a.Calculate which one of the reactants will be used up if 20g of Fe is mixed with 10g of S and heated. b.How many grams of the other reactant were in excess?
*October 10, 2011 by Heather*

**Chemistry**

3NO2 + H2O = 2HNO3 + NO How many grams of nitrogen dioxide are required to produce 5.89 x 10 to the 3rd power kg HNO3 in excess water?
*December 1, 2011 by Katelyn*

**chemistry**

How many grams of chlorine gas could be produced by the decomposition of 58.5g of sodium chloride according to the following equation.? 2NaCl = 2Na + Cl2
*December 14, 2011 by Jenna*

**chem**

How many grams of water vapor (H2O) are in a 10.2 liter sample at 0.98 atmospheres and 26°C? Show all work used to solve this problem.
*February 8, 2012 by alex*

**Chemistry**

If 25 grams of CoCl2•H2O,2 being the subscript of cl and the h, was heated to constant weight. What mass of anhydrous salt would remain?
*February 14, 2012 by Carrie*

**chemistry**

Al2O3(s)+6NO(g)---->5N2(g)+6H2O(l) how many grams of Nitric Oxide are required to produce 145g of nitrogen in the following reaction?
*February 27, 2012 by Mandy*

**Chemistry**

If 2 grams of acetic acid is reacted with excess 1-pentanol, what mass of pentyl acetate would you expect to achieve theoretically?
*April 10, 2012 by Leon*

**AP Chem**

How many liters of carbon dioxide will go into the air when 642.9 grams of gasoline (C8H18) is burned in complete combustion at STP?
*June 18, 2012 by Nihar*

**Chem.**

2KClO3 (s) ---> 2KCl (s) + 3O2 (g) For every mole of KClO3 that decomposes in the above experiment, how many grams of oxygen gas are produced? A.) 3 B.) 16 C.) 48
*September 29, 2012 by Anonymous *

**chemistry**

I need to determine how many grams of Cesium Iodide following solutes would be needed to make 5.00 102 mL of a 0.300 M solution.
*October 1, 2012 by Shawn*

**chemistry**

If a current of 5.0 Amps is passed through the electrolytic cell for .5 hour, how should you calculate the number of grams of bromine produced?
*October 26, 2012 by Chris*

**Chemistry**

How many grams of KNO3 (molar mass = 101.103 g/mol) should be used to make 325.0 ml of 0.070 M solution?
*November 5, 2012 by Timothy*

**Math**

How many grams in 23 kg? 23000? How many meters in 2 km? 2000? How many cm in 89m? 8900? How many mL in 25 L 25000? How many m in 7km 7000? How many mg in 10 g? 10000? HOw many mm in 15 m? 15000? How many km in 2500 m? 25? How many L in 10000mL? 10?
*January 10, 2013 by Jerald*

**chemistry**

what is the mass of the precipitate formed when 45.0 milliliters of .250 M barium chloride solution reacts with 2.00 grams of copper(II) sulfae pentaydrate?
*January 24, 2013 by jessica*

**math**

assume the substance has a half-life of 11 years and the initial amount is 126 grams.How long will it be until only 15 % remains?
*January 25, 2013 by Jackie*

**Chem II**

How many grams of ethylene glycol (C2H6O2) per kilogram of water are needed to give protection up to 120 °C in a car radiator?
*February 12, 2013 by jenny*

**chemistry**

if 125g of magnesium sulfate heptahydrate is completely dehydrated, how many grams of anhydrous salt will remain? i would really appreciate anyone's help
*February 21, 2013 by rose*

**chemistry**

Determine the amount (in grams) of boron that when substitutionally incorporated into of silicon will establish a charge carrier density of carriers/cm .
*April 1, 2013 by adex*

**science**

Calculated how many grams of methane (CH4) are in a sealed 80 mL flask at room temperature (22ºC) and 780 mm Hg of pressure. Show all your work.
*April 15, 2013 by bob*

**Chemistry**

How many grams of sodium acetate, NaC2H3O2, would have to be added to 5.00 L of 0.65 M acetic acid (pKa 4.74) to make the solution a buffer for pH 4.00?
*April 24, 2014 by Anonymous*

**Chemistry**

what is the specific heat of an unknown substance of 2000 j of energy required to raise the temperature of 4 grams of substances 5 degrees celsius
*April 30, 2014 by Tyran Wilson*

**chemistry**

An analytical procedure requires a solution of chloride ions ,How many grams of CaCl2 must be disolved to make2.15L of 0.0520 M C
*October 12, 2014 by mathew*

**Chemistry**

How many mL of 0.122 M Na2CO3 would be needed to precipitate all of the copper ions in 23.7 mL of 0.167 M CuSO4? How many grams of CuCO3 could be recovered?
*November 4, 2014 by Shelby*

**Chemistry**

How many grams of nitric acid (HNO3) must be dissolved in 590 ml of water to make a solution with a pOH = 10.1? Select one: a. 2.9 x 10-9 g b. 7.9 x 10-3 g c. 4.7 x 10-3 g d. 7.9 x 10-6 g e. 7.4 x 10-5 g
*November 23, 2014 by Bill*

**Chemistry**

4P + 50_2 ---> 2P205 25.4g of P are used with excess 02 how many grams of p205 should theoretically form I have no idea where to start im lost
*November 25, 2014 by Shawn*

**chemistry**

22.0 grams of zinc reacted with 95.0 mL of 0.5 Molarity HCl. What volume of hydrogen gas would be produced at 22 degrees C and 745 torr?
*January 5, 2015 by Madison*

**chemistry**

How many grams of calcium carbonate would it take to neutralize if i have 10ml 3 molar sulfuric acid? (can this be explained in detail?)
*February 10, 2015 by william *

**chemistry**

Find the mass in grams of a 240 ml sample of dry air at a pressure of 750 mmHg and a temperature of 19 degrees celsius.
*February 19, 2015 by Kimmy*

**Chemistry**

A 35ml 0.1M AgCl solution is mixed with 15ml 0.25M MgCl2 solution. Calculate the moles and molarities of the Ag+, NO3-,Mg2+, and Cl- ions in the solution mixture.
*September 1, 2008 by Jimmy*

**Chemistry**

If you needed 2.50g of CuSO4 for a reaction but only had CuSO4 * 5H2O available, how many g would you need to use to get the same number of moles of CuSO4?
*May 3, 2010 by Danny*

**Chemistry**

A sample of natural gas at STP is 78% CH4 and 22% C2H6 by volume. How many moles of each gas are present in 1.60L of the mixture? Assume ideal gas behavior
*October 6, 2010 by Missy*

**chemistry**

In a combustion reaction, propane (C3H8) reacts with oxygen. How many moles of CO2 can be produced when 2.25 mol of C3H8 react? C3H8(g) + 5O2(g) -„³ƒn3CO2(g) + 4H2O(g)
*January 19, 2014 by kita*

**chem**

A solution is prepared by dissolving 0.87mol of MgCl 2 in 0.40kg of water. How many moles of ions are present in solution? What is the change in the boiling point of the aqueous solution?
*March 26, 2015 by dakota*

**Chemistry**

I have 3 I don't understand how to do. A 33.2 g of iron ore is treated as follows. The iron in the sample is all converted by a series of chemical reactions to Fe2O3. The mass of Fe2O3 is measured to be 12.3 grams. What was the percent iron in the sample of ore? Answer in ...
*September 21, 2012 by Brett*

**Chemistry**

A certain mine produces 2.5 108 kg of copper from chalcopyrite (CuFeS2) each year. The ore contains only 0.80% Cu by mass. (a) If the density of the ore is 2.0 g/cm3, calculate the volume of ore removed each year. (b) Calculate the mass of SO2 produced by roasting (assume ...
*April 13, 2007 by Chemistry*

**Chemistry: Answer check please!**

1. Reactions follow the law of conservation of mass. a.) True b.) False Answer: True 2. Reactants are the materials used in a chemical reaction. a.) True b.) False Answer: True 3. In a chemical equation, the mass on the left of the arrow equals the mass on the right. a.) True ...
*April 2, 2011 by Cheryl*

**grammar**

Choose the best answer: 1. The L-1, along with the L-3 and L-4, ( show, shows, showing ) some sign of degeneration. Answer: show 2. She did not know (whom, who, whomever) to see about the recurrent congestion. Answer: who 3. The patient's physician contacted the ...
*May 12, 2011 by Leslie*

**physics**

Vector V represents a displacement of 120 km at 29.0 degrees counterclockwise from the x axis. Write V in unit vector notation. Express your answer using three significant figures. V= _______ km i know the answer should be Vx=120cos29 and Vy=120sin29 but the question requires ...
*September 21, 2011 by GV*

**Chemistry**

I need to calculate the molecular mass of ehtylene glycol based on the freezing point depression. The teacher said that for glycol i=1 and to use the equation m=delta T / Kf X i Kf = -1.86C/m so I did -2.5C / -1.86 X 1 = 1.344 I know that 1.344 can't be the weight for glycol ...
*February 21, 2012 by Hannah*

**Physics**

A steam engine goes through the following 3 step process. I) Isobaric compression from a volume of 100 L to 10 L at a pressure of 4 x 105 Pa II) Isovolumetric process from a pressure of 4 x 105 Pa to a pressure of 4 x 106 Pa at a volume of 10L. III) An isothermal expansion ...
*December 11, 2006 by Eric*

**math**

20.46 * 4 = 81.86 Round the answer to 1 decimal place what is the answer? My answer is 81.8 if not please tell me why and how?
*October 26, 2012 by May*

**Math Help**

Please help me solve these two problems and check my answer :) 1. 3x-5+x+2 My answer- X= 17/3 2. 5/6x+1/4= -9/4 my answer- X= -2
*February 9, 2014 by Unknown*

**algebra**

There are 50 questions to answer in a triva contest. Each player starts with 100 points. He or she earns ten points for each correct answer but will lose four points for each incorrect answer. Each player must answer all 50 questions. What is the fewest number of questions a ...
*October 4, 2011 by Anonymous*

**Math**

Part I: Statistical Measures Statistics is a very powerful topic that is used on a daily basis in many situations. For example, you may be interested in the age of the men who attend Silver’s Gym. You could not assume that all men are the same age. Thus, it would be an ...
*September 20, 2013 by Phylicia*

**quiz**

Question 1 Woodrow Wilson wished to keep the United States neutral at the outbreak of World War I primarily because h A)secretly admired German culture and the German university system. B) wanted to arbitrate among the combatants and to influence the settlement of the war. C) ...
*August 22, 2010 by paty*

**English**

Write the vocabulary word that goes with each idea. Glared - legendary - muttered - gaped -flinched- fluke - snickering - stunned. 1/.............stared at angrily. Answer: glared 2/..........something so great that stories are told about it. Answer:legendary 3/..........said ...
*October 15, 2014 by Nina*

**math**

can someone check this for me 11)Subtract 5/6 -3/5 My answer: .23 12)Add 1/3 + 1/5 + 1/10 My answer:.63 13) Divide .write each result in simplest form: 8/9 (divided by) 11/15 My answer: 1 and 1/20 5/6-3/5 is like saying: 25/30-18/30 = 7/30
*November 24, 2006 by Jasmine 20*

**calculus**

Could somebody please check these for me? Solve the differential equation with the given initial solution. 1. (dy/dx)=(-y/3) for y(0)=10 my answer was y=10e^(-x/3) 2. dP/dt=P+4 for P(0)=100 my answer was P=104(e^t)-4 3. dz/dt=te^z for z(0)=0 my answer was z=-ln(-.5(t^2)+1) THANKS
*April 14, 2008 by tia*

**calculus**

Could somebody please check these for me? Solve the differential equation with the given initial solution. 1. (dy/dx)=(-y/3) for y(0)=10 my answer was y=10e^(-x/3) 2. dP/dt=P+4 for P(0)=100 my answer was P=104(e^t)-4 3. dz/dt=te^z for z(0)=0 my answer was z=-ln(-.5(t^2)+1) THANKS
*April 16, 2008 by tia*

**spelling**

some people say cats have 9 of these answer: moms, dads, and children make up these answer: they are in-between words in a sentence answer:
*December 8, 2008 by Anya*

**literacy**

1Who narrates these poems? The Highwayman answer Robert W.service 2-The cremation of Sam McGee answer cap will 3-How I learned English answer
*April 10, 2009 by john*

**Calculus**

Find an equation of the tangent line to the curve f(x) = (sins)^2 + 2tanx at x= pi/4. I worked through it and got y = 5x + 5/2 for my answer, but the answer key says that it is y - 5/2 = 5(x - pi/4). Why is the pi/4 in the answer? Thanks for any help!
*October 19, 2014 by Lucy*

**CHEMISTRY**

Water has a van der Waals constants of a = 5.464 L·atm/mol2 and b = 0.03049 L/mol. What is the pressure of 5.20 moles of water vapor in a 1.10 L container at 100.0°C? I Dont understand this problem!
*May 10, 2009 by Kerrie*

**chemistry**

so i know that one mole is 6.022*10^23 particles in 12g of a carbon 12 isotope. im confused in finding the amount of moles in a particular substane. there is a formula that determines it, i think its n=m/M, yet im confused with what it means..
*May 19, 2010 by leana*

**Chem**

You are titrating an unknown weak acid you hope to identify. Your titrant is a 0.0935 mol/L NaOH solution, and the titration requires 22.3 mL to reach the equivalence point. How many moles of acid were in your sample?
*October 3, 2010 by Kim*

**chemistry**

Calculate the partial pressure of propane in a mixture that contains equal numbers of of moles of propane (C3H8) and butane (C4H10) at 20 degrees C and 844 mmHg. (R=0.082 L-atm/K mol)
*April 10, 2012 by Randy*

**chemistry**

You are titrating an unknown weak acid you hope to identify. Your titrant is a 0.0935 mol/L NaOH solution, and the titration requires 39.9 mL to reach the equivalence point. How many moles of acid were in your sample?
*October 2, 2012 by lucy*

**chemistry **

Given the reaction: H2SO4 = 2NaOH -> NaSO4 = 2H20. Determine the # of moles of sulfuric acid id needed to completely react with 2.3 L of 0.5 M of NaOH. Then determine the concentration of the solution if 3.0 L of it are used instead.
*November 4, 2012 by sarah*

**chemistry **

Given the reaction: H2SO4 = 2NaOH -> NaSO4 = 2H20. Determine the # of moles of sulfuric acid id needed to completely react with 2.3 L of 0.5 M of NaOH. Then determine the concentration of the solution if 3.0 L of it are used instead.
*November 4, 2012 by sarah*

**Chemistry**

at a pressure of 390.0 kPa, a sample of ideal gas containing 110. moles of propane is collected at a tempature of 55 degrees celcius. find the volume of the propane tank used
*February 25, 2013 by Elizabeth *

**Chemistry**

at a pressure of 390.0 kPa, a sample of ideal gas containing 110. moles of propane is collected at a tempature of 55 degrees celcius. find the volume of the propane tank used
*February 25, 2013 by Elizabeth *

**Intro Chemistry**

Given: 2CO(g) + O2(g) -> 2C02(g). When 10 mol of CO and 8.0 mol of O2 react in a closed 10L vessel. a)how many moles of CO, O2, and CO2 are present at the end of the reaction? b)What will be the total pressure in the flask at 0 degrees C?
*May 5, 2013 by Laichun*

**Chemistry**

How many moles of ammonia gas can be formed from the complete reaction of 44.8 liters of nitrogen gas at standard temperature and pressure (STP), according to the balanced equation, N2 (g) + 3H2 (g) arrow 2NH3 (g)?
*March 13, 2014 by Diana*

**Chemistry **

One mole of N2 and 3 moles of H2 are placed in a flask at 375 degree celsius.? Calculate the total pressure of the system at equilibrium if the mole fraction of NH3 is found to be 0.21. The Kp for the reaction is 4.21 x 10 raise to -4
*April 22, 2015 by Alex*

**Algebra 1**

Hello. Can someone check my answers to the following Factor each of the following 1. a^2 - 9 My answer a^2 - 9 = 0 (a - 3)a + 3) 2. 4a^2 - 4a+1 My Answer 4a^2 - 4a + 1 = 4a^2 - 2a - 2a + 1 = 2a(2a - 1) - 1(2a - 1) = (2a - 1)(2a - 1) 3. 72 - 22x + x^2 My answer 72 - 22x + x^2...
*May 20, 2010 by Tamir*

**Poetry meaning question..**

Hiya, I need some help for a poetry essay I have to write. Can you tell me what the line "darkness beneath nights darkness had freed, that rose slowly towards me, watching" might mean? I have no idea. What is the context of this? What is the title of the poem? The name of the...
*October 18, 2006 by Sarah*

**spanish**

IMPERFECTO o PRETERITO Termina las frases: 1. De nini, yo normalmente.... my answer pasaba el mato con mis amnigos 2. Yo hacias la tarea cuando de repente el telefono my answer sonabamos 3. Mis padres miriban la television cuando yo... my answer havegabamos internet 4. El ...
*January 10, 2009 by sam*

**Algebra**

Hi this question was already asked but there is still no correct answer. I can't seem to solve this for x correctly...I got 128 over 55 as an answer which can't be correct. Please help me find the correct answer! Thanks The equation is: .05x-.6(x+2)=.08 Please show the work as...
*October 12, 2011 by Clare*

**chemistry**

Soutions are made that contain 0.1 moles of each of the following compunds below in 100 of H2O. Choose the compounds whose solutions will have the lowest freezing point. A)MgCl2 B)MgSO4 C)KClO3 D)CO2 E)NaBr
*June 27, 2010 by jimbo*

**science**

if removed from the life cycle, which of the following would have the greatest impact on the productivity of lawns. 1. robins 2. moles 3. toadstools 4. dandelions 5. microrganisms i think 4 b/c of the seedd that are easily blown away in the wind to regerminate
*May 30, 2011 by John*

**Chemistry**

Solutions are made that contain 0.1 moles of each of the following compounds below in 100g of H20. Choose the compound whose solution will have the lowest freezing point? NaBr CO2 KClO3 MgCl2 MgSO4
*January 13, 2013 by Janet*

**Algebra**

Are these answer"s correct? What is the equation for the line that passes through the (-2,2) and has a slope of 5? Answer- Y=5x + 2 Y=5x +12 Y=5x -2 None of these ¨C I believe this is the answer Find the value of x^3+¡¼2x¡½^2-3 when x =3. Answer- 42 Solve 5x+3=13 for x. Answer...
*August 6, 2011 by lizzie*

**French**

Could you check these thanks: Directions: Vrai ou Faux? 1. Un film doublé a des sous-titres. Answer: vrai 2. Un film en version originale est toujours en français. Answer: faux 3. Au cinéma, il y plusieures séances le week-end. Answer: Faux 4. On peut louer des films en vidéo...
*November 30, 2009 by Maria*

**chemistry**

A helium balloon contains 0.26 g of helium. How many moles of helium does it contain?
*November 17, 2008 by pip*

**Chemistry**

Elemental sulfur occurs as octatomic molecules, S8. How many moles of fluorine gas, F2, are needed for complete reaction with 50.5 g sulfur to form sulfur hexafluoride? Do not enter units.
*September 9, 2011 by Aha*

**Chemistry**

Elemental sulfur occurs as octatomic molecules, S8. How many moles of fluorine gas, F2, are needed for complete reaction with 50.5 g sulfur to form sulfur hexafluoride? Do not enter units.
*September 9, 2011 by Aha*

**chemistry**

What is the formula weight of Li2CO3? 73.891 amu b. What is the mass of 1.30 x 10-4 mol of Li2CO3? 9.61E-3 c. How many moles of CO32- ions are present in 102 g of Li2CO3? Dont get how to compute
*February 8, 2012 by krystal*

**chemistry**

The rusting of iron is represented by the equation 4Fe + 3O2 2Fe2O3. If you have a 1.75-mol sample of iron, how many moles of Fe2O3 will there be after the iron has rusted completely?
*April 9, 2012 by gwen*

**Chemistry**

When iron rusts in air, iron (III) oxide is produced. How many moles of oxygen react with 7.2 mol of iron in the rusting reaction? 4Fe(s)+3O2=2Fe2O3(s)
*January 27, 2015 by Alex*

**Math**

HELP! can you check and help me with some of these? 1. y + 8 = -15 My answer: -7 2.3x = 27 My answer: 9 3. 5 + a = -19 My answer:-24 4. x + 1/3 = 5/6 My answer: NEED HELP WITH THIS ONE 5. -54 = -6y My answer: 9 6. a/3 = -11 My answer: -33 7.19.5 = -39.5 + f My answer: -20 8.p...
*August 18, 2011 by Bryce*

**Chemistry. Please help!!**

Calculate the final temperature when a 18.7 gram sample of ice at 0 degrees C is placed into a styrofoam cup containing 113 grams of water at 71.6 degrees C. Assume that there is no loss or gain of heat from the surroundings. Heat of fusion of ice = 333 Jg^-1 Specific heat of ...
*March 2, 2012 by JJ*

**chemistry**

If 4 moles of gas are added to a container that already holds 1 mole of gas, how will the pressure change inside the container?
*August 7, 2008 by natasha*

**Chemistry**

A dilute sulfuric acid solution that is 3.39 m H2SO4 has a density of 1.18 g/mL. How many moles of H2SO4 are there in 375 mL of this solution? 3.39 is 3.39 Molality not molarity
*February 23, 2010 by Nick*

**chemistry**

calculate the number of moles of carbon dioxide in a volume of 50.0 mL of carbon dioxide, assuming a pressure of 1.00 atm and a temperature of 23.0C
*July 27, 2010 by annie*

**chemistry**

How many moles of water will produced at equilibrium be if there is 1.0 mole of carbon dioxide formed at equilibrium? 2 C2 H6(g) + 7 O2(g) <==> 4 CO2(g) + 6 H2 O(g) ... [CO2]^4[H20]^6/[C2 H6]^2[O2]^7
*July 27, 2010 by Anonymous*