Monday

August 29, 2016
Number of results: 61,349

**chemistry**

How many grams of C6H12O6 need to be dissolved in 350g of water vto have a solution which freezes at -2.50 degrees celcius? delta T = Kf*m You know Kf, m = molality = mols/kg and mols = grams/molar mass, delta T is 2.50. Solve for grams. Post your work if you get stuck. what ...
*May 31, 2007 by jessica*

**CHEMISTRY**

how many grams of zinc are required to react with excess acid to make one liter of hydrogen at STP? i have no clue how to go about this i need help Write the balanced equation. Zn + 2HCl ==> ZnCl2 + H2 2. Use PV = nRT to convert 1 L H2 gas to mols OR take the shortcut ...
*April 23, 2007 by yellowone*

**Chemistry**

mass-mass conversions and mass-mole conversions: what is the difference and how do you do each? mass is converted to mols by mols = grams/molar mass. mass of one chemical is converted to mass of another chemical by using the coefficients in the balanced chemical equation. For ...
*January 18, 2007 by Briana*

**mixture**

Sugar solution is composed of 40 grams of sugar and 200 grams of water. How many grams of sugar must be added to make a 60% sugar solution? (Kindly write the equation..... tnx)
*November 22, 2012 by HELP HELP MNHS*

**Chemistry**

what is the total # of grams of NaOH(formula mass=40) needed to make 1.0 liter of a 0.20 M solution a. 80.g b. 2.0g c. 8.0g d. 20.g Go back to the molarity definition. is the answer b molarity = #mols/L 0.20 M means we want # mols in 1 L to be 0.20 mols. grams = mols x molar ...
*March 26, 2007 by Kat*

**chemistry**

how many grams of H2 (g) are produced by the reaction of 1.35 g Al with 75.0 mL of 3.44 M HCl Here is the way to do most of these stoichiometry/limiting reagent type problems. Step 1. Write a balanced chemical equation. 2Al + 6HCl ==? 3H2 + 2AlCl3 Step 2. Convert what you have...
*September 24, 2006 by brian*

**Chemistry**

If 20.0 grams of Al is placed into a solution containing 115 grams of H2SO4, how many grams of hydrogen gas could be produced? 1. Write the balanced equation. 2Al + 3H2SO4 ==> Al2(SO4)3 + 3H2 2. Convert 20.0 g Al to mols. Remember mols = g/atomic mass 3. Using the ...
*March 18, 2007 by Britney*

**chemistry**

N2 + 3H2 --> 2NH3 how many grams of hydrogen are needed to react with 50 grams of nitrogen? Three moles of H2 per one mole of N2. How many moles of N2 is 50 grams? 1.79 moles is 50 grams. You do these problems in steps. Step 1. Write a balanced chemical equation. You have ...
*June 22, 2006 by Hawk*

**Help now please, Chemistry**

How many grams of oxygen can be produced by heating 10.0g of mercury (II) oxide? Sulfuric acid is added to 8.10g of magnesium, how many grams of hydrogen are set free? I'll do the first. You do the second by following the first as a guide. 1. Write the balanced equation. 2HgO...
*March 5, 2007 by Beautiful*

**science**

How many grams of hydrochloric acid are required to react completely with 4.30g of zinc? How many molecules of gas will be produced? 1. Write the balanced chemical equation. Zn + 2HCl ==> ZnCl2 + H2 2. Convert grams Zn to mols. mols = grams/atomic mass Zn. 3. Using the ...
*March 17, 2007 by Josh*

**chemisty help**

for the reaction shown, compute the theoretical yield of the product in grams for each of the following initial amounts of reactants. Ti + 2F2 to make TiF4 There are 3 sub questions for this. Help me out with one, then I'll try to figure out the rest. thanks a) 4.8g Ti; 3.2gF2...
*March 1, 2007 by Becky*

**chem**

For the reaction 3NO2 + H2O 2HNO3 + NO, how many grams of HNO3 can form when 1.00 g of NO2 and 2.25 g of H2O are allowed to react? This is a limiting reagent problem. 1. Write the equation. You have done that and it is balanced. 2. Convert 1.00 g NO2 and 2.25 g H2O to mols. ...
*February 28, 2007 by meghan*

**chemistry**

if 37.9 liters of NO at .993atm and 146 degrees celcius are decomposed by the reaction 2NO-->N2+O2 how many grams of nitrogen will be formed... could you show mw step bu step how to do this ? thanks....i have finals tommorrow.... i need HHHHHHEEEEEEELLLLLLPPPPPPPP PV=nRT P=...
*January 10, 2007 by TIFFANY*

**chemistry**

determine the number of grams of NH3 produced by the reaction of 3.5g of hydrogen gas. 1. Write the equation and balance it. N2 + 3H2 ==> 2NH3 2. Convert 3.5 g H2 gas to mols. mols = grams/molar mass. 3. Convert mols H2 gas to mols NH3 using the equation from step 1. 4. ...
*August 11, 2007 by danni*

**chem**

I can't seem to figure this out! I know I have to use mass to mass conversions though. Can someone help me out? Hydrochloric acid can dissolve solid iron according to the following equation: Fe + 2HCl to form FeCl2 + H2 a) How much HCl in grams would you need to dissolve a 2.8...
*March 1, 2007 by Abby*

**Chemistry**

Determine the number of grams of NH3 produced by the reaction of 3.5g of hydrogen gas with sufficient nitrogen gas. All of these stoichiometry problems are work almost the same. Sometimes an extra step or two are required. Here are the basics. Step 1. Write the balanced ...
*January 23, 2007 by Sara*

**chemistry**

how many grams of glucose C6H12O6 would you need to make 250 mL of 1.0 M solution?
*April 28, 2011 by amber *

**science**

How many grams of glucose C6H12O6 would you need to make 250 mL of 1.0M solution?
*May 29, 2013 by kevin*

**chemistry(DrBob222)**

did you read my previous post? I just want to mke sure understand what the answer is I think it's 1.11 No, the answer is 2.22 grams. 1.11 is the number of mols H2 which you calculated correctly. Then you converted 1.11 mols to grams by 1.11 mols H2 x molar mass H2 = 1.11 mols ...
*May 15, 2007 by mike*

**algebra**

Jessica is baking a cake. The recipe says that she has to mix 96 grams of sugar to the flour. Jessica knows that 1 cup of this particular sugar has a mass of 128 grams. She added one over two of a cup of sugar to the flour. Should Jessica add more sugar to make the exact ...
*September 9, 2014 by Anonymous*

**Chemistry 1 H**

AgNO3+ BaCl2-> AgCl+ Ba(NO3)2 a. balence the equasion b. How many grams of silver chloride(AgCl) are produced from 5.0g of silver nitrate (AgNO3) reacting with an excess of barium chloride(Ba Cl2)? c. How Many grams of barium chloride (BaCl2) is necessary to react with 5.0...
*January 4, 2007 by Lexi*

**Chemistry**

What preperation produces a 2.0 Mole solution of C6H12O6? a) 90.0 grams of C6H12O6 dissolved in 500.0 mL of solution b) 180.0 grams of C6H12O6 dissolved in 1000mL of solution c) 90 Grams of C6H12O6 dissolved in 1000mL of solution D) 180.0 Grams of C6H12O6 dissolved in 500.0mL ...
*December 19, 2012 by D*

**science**

How many grams of Aluminum will react w/ 1 liter of a 1M solution of Fe^3+? wat steps do i need to take to solve this? Al + Fe+3==> Fe+2 + Al+3. Here are the steps for solving a stoichiometry problem. Step 1. Write the balanced equation. You have the equation; it must be ...
*January 3, 2007 by michelle*

**biology**

Why is CO^2 required by plants to produce glucose? ( the arrow pointing up should be pointed down.) CO2 is where the Carbon comes from to make sugar.Glucose is a six-carbon sugar represented by the formula C6H12O6
*January 4, 2007 by marco*

**chem 103**

Still stuck on this question. How many grams of Na3PO4 would you need to make 0.225L of 8.0M stock solution? 8.0 M of NaPo multiplied by .225L NaPO = 1.8 mols of Na3PO4. Then multiply the 1.8 mol times the mass of Na3PO4 which is 163.93 grams?, yes? This would make 295.07 ...
*July 14, 2013 by Andrew*

**chem**

Forty-two grams of benzoic acid is treated with concentrated nitric acid in some sulfuric acid. Forty-two grams of the major expected organic product is isolated. What is the percentage yield for this experiment? Give an equation with structural formulas for the major reaction...
*August 6, 2007 by Damon*

**chem 2**

what is the mass of F in grams in 24.6 grams of SnF2? Convert 24.6 g SnF2 to mols SnF2. Convert mols SnF2 to mols F atoms. Convert mols F atoms to grams F atoms. 24.6 g SnF2*(1 mol SnF2/molar mass SnF2)*(2 mols F/1 mol SnF2)*(atomic mass F/1 mol F Atoms) = ?? Check my thinking...
*July 16, 2007 by christine*

**chemistry**

Aluminum reacts with sulfuric acid, which is the acid in car batteries. If 20.0 grams of Al is placed into a solution contain 115 gram of H2SO4, how many grams of hydrogen ga could be be produced? 2Al + 3H2SO4 ---> Al(SO4)3 + 3H2 20.0g/27 = .741 .741 X 3/2 = 1.11 1.11 X 2...
*May 15, 2007 by mike*

**chemistry**

How many grams of NaCl should be added to 250 grams of water to make a 0.40 m solution? I got 19 grams. this is how I got it. first I found the mass of water = 18g then I converted that to mols 18/250 = .0072. I subtracted 0.072 - 0.40 = 0.328 I found the mass of NaCl = 58 0....
*March 24, 2007 by davis*

**CHem Part 2**

Part of the SO2 that is introduced into the atmosphere by combustion of sulfur containing compounds ends up beingh converted to sulfuric acid. 2SO2 (g) + O2 (g) ---> 2H2SO4 (aq) How much sulfuric acid can be formed from 5 moles of SO2, 2 moles of O2 and an unlimited ...
*November 1, 2006 by Kim*

**chemistry 1**

if 20.2g of zn react with and equal amount of magnesium chloride to form magnesium and zinc chloride[zn+mgcl2> mg+zncl2] a.what is the limiting reactant? b. how much magnesium will be produced? Here is the way to solve most of these stoichiometry problems. Step 1. Write the...
*May 11, 2007 by sam*

**chemistry**

In the lab, 20.0 g of sodium hydroxide is added to a beaker giving it a total mass of 128.4 g. Sulfuric acid is added until all of the sodium hydroxide reacts. After heating, the total mass of the beaker and the dry compound is 142.3 g. Caculate the percent yeild. 2NaOH + ...
*June 13, 2007 by jill*

**Pre AP Chemistry**

If I have a 1200 gram sample of a soft drink and it contains 180 grams of sugar, the percentage by mass of the sugar in the drink is 15%. If the sugar in the drink is sucrose (C12H22O11), how many grams of pure carbon can be obtained from decomposing all of the sugar in the ...
*February 22, 2011 by Lynn*

**chemistry**

how to calculate grams in carbon dixoide?? grams = mols x molar mass grams CO2 = mols CO2 x 44
*November 17, 2006 by Cindy*

**Chemistry**

Determine the number of grams of NH3 produced by the reaction of 3.5g of hydrogen gas with sufficient nitrogen gas 1. Write the balanced equation. 2. Convert what you have (3.5 g) into mols. Mols = grams/molar mass. 3. Use the coefficients in the balanced equation to convert ...
*March 11, 2007 by Roxxanne*

**Chemistry**

I was wondering if you could help me with this problem. If the reaction proceeds with a 96.8% yield, how many kilograms of CaSO4 are formed when 5.34 kg SO2 reacts with an exfess of CaCO3 and O2? Thanks for your help. Write the equation for the reaction and balance it. CaCO3...
*July 9, 2007 by Ally*

**Stoichiometry problem**

I'm stuck and am hoping you can help. Here is the problem: You react 7.92 grams of silver nitrate, AgNO3(aq), with an excess of sodium chloride, NaCl(aq). How many grams of silver chloride, AgCl(s), will precipitate from the solution? Any help would be appreciated. Most of ...
*September 9, 2006 by Rachel*

**Chemistry**

I need help on this stoichiometry problem. I don't know whay my answer is incorrect. The fermentation of sugar to produce ethyl alcohol occurs by the following reaction: C6H12O6 -- 2C2H5OH + 2CO2 What mass of ethyl alcohol can be made from 1.00 kg of sugar? I keep getting 1012...
*September 28, 2010 by Deni*

**Setting up a chem problem**

Magnesium reacts with water in the equation, Mg+2H²O-->Mg(OH)²+H². You have 8.1 g of magnesium available. This means you will need ___ g of water to use all the magnesium. This seems sorta simple, but how can i set it up? These are stoichiometry problems. They can be solved...
*January 18, 2007 by Briana*

**AP Chemistry**

What percent (by mass) of granulated sugar is fructose, and what percent of it is sucrose? Background: We are doing a colligative properties lab in my class where we are to add 20 grams, 40 grams, 60 grams, and 80 grams of sugar to 100 grams of water, and use the change in the...
*December 6, 2014 by David*

**Chemistry**

If one gram of sodium bicrbonate made it into your stomach from 1 teaspoon of baking soda, how many moles of acid could it neutralize? mols NaHCO3 = grams/molar mass. mols HCl=mols HCO3%-
*February 20, 2007 by Bob*

**physical science**

how much sugar is dissolved in 500 grams of a solution if the solution is 70 percent sugar by mass? Also, What is the concentration of a solution that contains 45 grams of sugar in 500 grams of solution? thank you
*December 28, 2008 by Lisa*

**Chem help!!**

A rock salt (NaCl), ice, and water mixutre is used to make homemade ice cream. How many grams of rock salt must be added to lower the freezing point 10.0 degrees C? I have no idea what to do, please help! delta T = Kf*i*m delta T = 10. Kf is the molal freezing point constant, ...
*May 3, 2007 by Lindsay*

**Chem 011**

I can not figure out how many mols are in 102grams of NH3? mols = grams/molar mass. mols NH3 = 102/17 = ??
*April 10, 2007 by Stephanie*

**chemistry**

A compound has the following composition. C 54.5%, H 9.10% and 0 36.4% its molecular weight is 88.10. Determine its empirical formula and molecular formula. Take 100 g sample. That gives you 54.5 g C, 9.10 g H and 36.4 g O. Now convert those grams to mols. 54.5/12.01 = mols C ...
*June 24, 2007 by Brooke*

**chem**

assuming you have o.4g of Y(OH)3, calculate the mass of Ba)2 required to produce YBa2Cu3O7. Is that BaO2 for Ba)2? Is that really BaO2 or BaO. BaO2 is barium peroxide, not oxide. Y(OH)3 ==> YBa2Cu3O7 Step 1. Convert 0.4g Y(OH)3 to mols Y(OH)3. Step 2. Multiply by 2 to ...
*October 24, 2006 by nick*

**For DrBob222**

I'm not surprised the answer was wrong. Chemical reactions are by mols and not by grams; therefore, 1 mol of each reactant produces 1 mol of each product but a mol is not a gram. SO, convert 0.5839 g KHC2O4 to mols, convert mols KHC2O4 to mols KOH (that's the 1:1 part), then ...
*January 9, 2008 by Andrew*

**Chem**

Nitric acid is produced commercially by the Ostwald process, represented by the following equations: 4NH3(g) + 5O2(g) > 4NO(g) + 6H2O(g) 2NO(g) + O2(g) > 2NO2 (g) 3NO2(g) + H2O(l) > 2HNO3(aq) + NO(g) What mass of NH3 must be used to produce 1.0x10^6 kg HNO3 by the ...
*January 26, 2007 by Shawn*

**"Given Molality, calculate..."**

"Given: An aqueous solution of C6H12O6 with a density of 1.18 g/ml" I) Calculate Molarity 1) It firsts asks me to, "State the moles of solute" 2) Calculate the mass of the solute in grams - I think I can do this if I know how to get #1 3) Later it also asks, "State the ...
*November 19, 2006 by Rachel*

**chemistry**

105 grams of MgCl2 contains how many mols of MGCl2? mols = grams/molar mass Better get your calculator.
*February 7, 2007 by larry*

**chemistry**

if C6H12O6 -> 2 C2H5OH + 2 CO2 represents the fermentation of sugar to produce alcohol, and the reaction is only 40.0% efficient (% yield), what is the actual yield of alcohol from 454 g of C6H12O6
*November 30, 2010 by lianne*

**chemistry**

how many moles of sugar are contained in a 10-lb bag of sugar if sugar has formula C12H22O11? first convert the pounds into grams, then grams into moles.
*December 1, 2012 by Deidra*

**chem**

An automobile burns 65 grams of gasoline over 20 minutes. The gasoline combines with 100 grams of oxygen in this reaction, to form carbon dioxide and 47 grams of water. How much carbon dioxide is formed? do I use the heat capacity equation? How much oxyen is used to produce 47...
*February 14, 2007 by tina*

**Chemistry**

1.) How many grams of 2-propanol are expected from the complete reaction of 672 g of propene? 2.)How many moles of propane are expected from the complete reaction of 82.8 g of propene? 3.)How many grams of propane are expected from the complete reaction of 101 g of propene? 4...
*April 5, 2007 by Kira*

**Chemistry**

The average human requires 120.0 grams of glucose (C6H12O6) per day. How many grams of CO2 ( in the photosynthesis reaction) are required for this amount of glucose? The photosynthetic reaction is: 6 CO2 + 6 H2O = C6H12O6 + 6 O2
*January 19, 2011 by Artie*

**Algebra**

A 12oz can of soda contains 40 grams of sugar. How many grams of sugar does a 70 oz bottle contain?
*March 1, 2016 by Whatt*

**Chemistry**

From this equation, how many glocose does the human body consume ineach minute? If gram per mole is 180.16. The human body needs at least 0.0103 mole O2. Equation C6 H12 O6 + 6O2-->6CO2 +6HO2 How many glucose what? grams? moles? tons? Mext, the human body needs at least 0....
*March 25, 2007 by Jerremy*

**chemistry**

What mass in grams of potassium hydroxide is cntained in 500 mL of solution that has a pH of 11.5? For Further Reading chemistry - DrBob222, Sunday, April 6, 2008 at 12:09am pH = 11.5 pOH = 14 - 11.5 = 2.5 pOH = -log(OH^-) ] 2.5 (OH^-) = ?? KOH ==> K^+ + OH^- This is a ...
*April 6, 2008 by Sarah*

**CHEMISTRY**

4NH3 + 7O2 = 4NO2 + 6H2O HHOW MANY MOLES OF AMMONIA WILL BE REQUIRED TO PRODUCE 10.0 MOLES OF WATER? The equation tells you 4 mols NH3 will produce 6 mols H2O. Can you set up a proportion to make that work? For example, 2 mols NH3 would produce 3 mols H2O and 8 mols NH3 would ...
*July 17, 2007 by Janice*

**chemistry**

from the balanced equation 4NH3 +7O2 - 4NO2 + 6H2O How many molecules of water are produced when 2.25 moles of ammonia are completely reacted? The equation tells us that 4 mol NH3 will produce 6 mols water. That means 2 mols NH3 will produce 3 mols water. How did we do that? 2...
*March 18, 2007 by jessica*

**Chem**

If you start with 3.500 g of ZnSO4 (Zinc Sulfate) & 7 H2O and heat it for 10+ minutes to remove the water of hydration, what will be the mass of water removed? Hint: Since you know the number of grams of hydrated salt present you then know the number of moles. Once you know ...
*February 18, 2007 by Angie*

**science**

Posted by Josh on Saturday, March 17, 2007 at 10:58pm. How many grams of hydrochloric acid are required to react completely with 4.30g of zinc? How many molecules of gas will be produced? For Further Reading science - DrBob222, Saturday, March 17, 2007 at 11:07pm 1. Write the ...
*March 18, 2007 by Josh*

**chemistry**

Calculate the concentration in molarity of sugar in a solution made by dissolving 0.34 moles of dextrose (C6H12O6) in enough water to make 3.00 Liters of solution
*December 2, 2011 by Seep*

**Math **

Karol bought 1lb of sugar. She used 1/4 lb of sugar to bake a big cake and some of the remaining sugar to make lots of cookies. She had 3/8 lb of sugar left. How much sugar did Karol use for the cookies? I came up with 3/8-1/4=3/8-2/8=1/8 lb
*March 24, 2015 by Reine Meghan *

**chemistry**

What mass in grams of potassium hydroxide is contained in 500 mL of solution that has a pH of 11.5? I have a pOH of 2.5 to get [OH] I do 10^-2.5 to get 0.001581138 Then I divide this by 2 to find the mols in 500 mL Then, grams = mols x molar mass = 0.00158``38 x 56.105 g/mol =...
*April 7, 2008 by Dustin*

**algebra**

The manager of the school cafeteria is planning a plate lunch. She can spend no more than $2.00 per lunch and can choose servings from selections A and B. The table indicates the cost and the quantity of sugar and protein (in grams) per serving of each food choice. Food Cost ...
*March 30, 2015 by Clara*

**Chemistry**

Calculate the number of grams necessary of C6H12O6 to make 1.00 ml of 0.025 M glucose.
*September 14, 2012 by Anonymous*

**Chemistry**

How many grams of C6H12O6 must be added to 0.750 kg of water to make a 1.25 m solution?
*March 20, 2013 by Samantha*

**science**

how do i calculate the mols of sulfuric acid ? mols = grams/molar mass
*February 7, 2007 by Deon*

**Chemistry**

is there an equation to find mass percent....if know concentration and and final and initial volume of a titration lab? there isnt one then how do you find mass percent? M x L = mols of titrant. From the equation, convert to mols of unknown. Mols of unknown x molar mass = ...
*May 7, 2007 by Natalie*

**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**

0.2 Grams of HCL is dissolved in 0.8g of water. The density of the solution formed is 1.10g/ml. What is the molarity of the solution???? %HCl = [0.2/0.2+0.8)]x100 = 20% Density = 1.10 g/mL. The mass of 1,000 mL is 1.10 g/mL x 1,000 mL = 1100 grams. Mass HCl in the 1100 g is ...
*February 5, 2007 by boo*

**Chemistry**

How many moles of propane are expected from the complete reaction of 82.8 g of propene? How many grams of propane are expected from the complete reaction of 101 g of propene? Kyle-- Here is a problem I worked last night for Kira (about half way down the page). It should give ...
*April 5, 2007 by Kyle*

**Chemistry**

In winemaking, the sugars in grapes undergo fermentationby yeast to yield CH3CH2OH and CO2. During cellularrespiration, sugar and enthanol are "burned" to water vapor andCO2. A) Using C6H12O6 for sugar, calculate ÄH of fermentation and of respiration(combustion). B) Write a ...
*October 24, 2015 by Mark*

**Math**

Ricky needs 3 1/4 cups of sugar to make candy. He already has 2 1/2 cups. How many more cups of sugar does he need? Do you add for this question or subtract? That's all that I need to know.
*March 26, 2015 by Zoe*

**chemistry**

Which of the following would have the lowest vapor pressure? A. 0.8 m C6H12O6 B. 0.10 m C6H12O6 C. 0.05 m C6H12O6 D. 0.15 m C6H12O6 I think it is D... is that correct? Which of the following would have the lowest boiling point? A. 0.8 m C6H12O6 B. 0.10 m C6H12O6 C. 0.05 m ...
*November 12, 2009 by Christina*

**8th grade math**

Can you please check my answer? Marcia wants to make muffins and needs 3/4 cup of a cup of sugar. She discovers, however,that she has only 2/3 of a cup of sugar. How much more sugar does she need? my answer: 1/12 of a cup
*November 8, 2010 by Elizabeth*

**chemistry**

Hi. I'm not sure if my strategy for this problem is correct: How many grams of CaCO3 will dissolve in 3.0x10^-2 mL of 0.050M Ca(NO3)2? I think I'm supposed to convert molarity of Ca(NO3)2 into moles, but then i don't know how to get from mols of that to mols of CaCO3..is it a ...
*May 17, 2008 by Amir*

**chemistry**

The fermentation of sugar (C6H12O6) to form ethanol (C2H5OH) and carbon dioxide (CO2) occurs according to the following equation: C6H12O6(aq) ¡ú 2 C2H5OH(aq) + 2 CO2(g) kJ mol¨C1 ¦¤Hf (C6H12O6(s)) is ¨C1275 ¦¤Hf (C2H5OH(l)) is ¨C277 ¦¤Hbond (C=O) 799 (a) Assuming the heat of ...
*November 3, 2010 by mailyn*

**Chemistry**

Zn + PbCl2 --> ZnCl2 + Pb The initial mass of a zinc strip is 2.684. After being left overnight in a lead (II) chloride solution, the mass of zinc is 2.581g. Calculate the Ksp of lead (II) chloride. So far I have: PbCl2 --> Pb(aq)2+ + 2Cl(aq)- Ksp = [Pb(aq)2+] [Cl(aq)-]^...
*May 23, 2007 by Raj*

**Pre-Algebra**

To make a batch of cookies you need 3.25 cups of sugar, if you start off with 16.5 cups of sugar, how many batches of cookies can you make?
*January 17, 2013 by Gianna*

**CHEMISTRY HELP!!!!!!!!**

How many grams of KCl are produced by the thermal decomposition of KClO3 that produces 25mL of O2 at 25 degrees and at 1 atm? A)0.0508 B)0.0762 C)0.0835 D)0.125 what is the anwser and what equation would i use to get the anwser? Write the balanced equation for the ...
*April 21, 2007 by smartypants*

**Math**

Grandma needs 13/4 cups of sugar to make a dozen cookies. How much sugar does she need to make 3 dozen cookies?
*November 28, 2015 by Yolanda*

**Chemistry**

I would really aprreciate if someone could help me, thank you so much. The white limestone cliffs of Dover, England, contain a large percentage of calcium carbonate(CaCO3). A sample of limestone weighing 84.4g reacts with an excess of hydrochloric acid to form calcium chloride...
*July 9, 2007 by Amy*

**4th grade**

You need 1/2 cup of sugar to make a three-layer cake. How much sugar would you need for a one-layer cake? Can you help me...thank you
*November 30, 2009 by Mia*

**4th grade**

You need 1/2 cup of sugar to make a three-layer cake. How much sugar would you need for a one-layer cake
*February 11, 2010 by Scott*

**Chemistry**

A mettallurgist decided to make a special alloy. He melted 30 grams of Au(Gold) with 30 grams of Pb. This melting process resulted to 42 grams of an Au-Pb alloy and some leftover Pb. This scientist wanted to make 420 grams of this alloy with no leftovers of any reactants. how ...
*October 31, 2011 by Eli*

**math**

You need 1/2 cup of sugar to make a three layer cake. How much sugar would you need for one-layer cake?
*November 29, 2012 by emma*

**Math**

You need 1/2 cup of sugar to make a three layer cake.how much sugar would you need for one layer cake?
*November 25, 2013 by Pietro*

**nutrition**

A food product claiming to be sugar free contains A. less than 10 grams of sugar per serving. B. less than 0.5 grams of sugar per serving. C. less than 5 milligrams of sugar per serving. D. less than 2 milligrams of sugar per serving.
*October 19, 2015 by yourmom*

**Chemistry**

Can you show me how to do this? 2KClO3 -> 2KCl + 3O2 If 5.0(g) of KClO3 is decomposed , what volume of O2 is produced at STP? 5 g KClO3 = ?? mols. ??mols KClO3 will produce how many mols O2? Use the coefficients in the equation to do this conversion. 1 mol O2 occupies 22.4 ...
*January 10, 2007 by Tabby*

**Math**

The ratio of the quantities of sugar and flour needed to bake a cake is 2:5. What is the quantity of sugar needed for a cake, if 750 grams of flour are used to make it?
*November 16, 2015 by Amy*

**Science**

How much sodium hydroxide, at what concentration, do I need to add to 500 mL of 0.1 N HCL to obtain pH 6.8. How do you calculate this? pH = -log(H^+) M HCl = N HCl mols = M x L. After you know mols HCl you have, then make a solution of NaOH and calculate how much of that must ...
*February 5, 2007 by Ruby*

**math**

a muffin recipe calls for 4 cups of sugar and yields 36 muffins. if amelia only wants to make 24 muffins, how much sugar will she need?
*December 26, 2014 by anonymous*

**Math**

If a recipe calls for 2/3 cups of sugar but I only want to make 1/4 of the recipe, how much sugar do I need?
*July 22, 2015 by Sam*

**chemistry**

Need help stepping through this for a review. I need to prepare 40grams of a 29% sugar solution. How do I calculate how much sugar and how much water is needed? Was given this formula: weight% (w/w)=100 * (mass of solute/total mass of solution) I set up my problem: .29 = 100...
*February 3, 2015 by j3z*

**chem - br bob is this right**

What is the pH of a solution prepared by adding 4.000 grams of NaOH to a 50.00 mL of a buffer that is 2.00 molar both in acetic acid and sodium acetate? (Assume final volume is still 50.00 mL) * chem - DrBob222, Wednesday, April 21, 2010 at 10:52pm * chem - phil, Wednesday, ...
*April 21, 2010 by phil*

**in response to Tabby**

so in order to find out how many moles of O2 are produced from 12 moles of KClO3: 2 mols KClO3 form 3 mols O2 4 mols KClO3 form ? mols O2 Do you double the mols of O2 4 mols KClO3 form 6 mols O2? 6 mols KClO3 form 9 mols O2
*January 24, 2007 by iearn*

**Stoichiometry**

How many grams of ZnO is needed to make 6.8 g of ZnCl2. Change 6.8 g ZnCl2 to mols. One mol ZnO is needed to make 1 mol ZnCl2. Change mols ZnO to g ZnO. Post your work if you get stuck.
*December 1, 2006 by C.J.*

**chemistry ap**

Why would [23.8-(.0588)(23.8)] be the proper setup to determine the vapor pressure of a solution at 25 Celsius that has 45g of C6H12O6, glucose (MM=180gxmol^-1), dissolved in 72g of H2O? The vapor pressure of pure water at 25Celsius is 23.8 torr. vp pure solvent - lowering due...
*May 17, 2007 by alexa*