Recent Homework Questions About Chemistry
How many grams of K2Cr2O7 (Potassium dichromate) must be used to make 250 ml of a0.125 M solution?
Sunday, December 8, 2013 at 8:59pm
How do I balance this chemical reaction? __K + __CaBr2 → __KBr + __Ca
Sunday, December 8, 2013 at 8:56pm
Q2: A sample of carbon dioxide(CO2) has a mass of 55g and occupies 3.3L at 100C. What pressure does the gas exert (in kPa)?
Sunday, December 8, 2013 at 7:45pm
Q3: In the combustion reaction of 149g of propane(C3H8) with excess oxygen, what volume of carbon dioxide(CO2) is produced at STP? (note: balance the reaction first) C3H8 + O2 3CO2 + H2O
Sunday, December 8, 2013 at 7:44pm
Aluminum granules are a component of some drain cleaners because they react with sodium hydroxide to release both energy and gas bubbles to help clear the drain clog. The reaction is: 2NaOH + Al + 6H2O 2NaAl(OH)4 + 3H2 (note: balance the reaction first) What mass of ...
Sunday, December 8, 2013 at 7:43pm
for a thermodynamics lab, I have to graph the ln K vs. 1/T, so does the ln K go on the y-axis and the 1/T go on the x-axis?
Sunday, December 8, 2013 at 7:26pm
What is the pH of a solution that results from adding 0.054 mol Ca(OH)2 to 1.76 L of a buffer comprised of 0.33 M CH3COOH and 0.33 M CH3COONa? I'm not sure how to start this. Thanks!
Sunday, December 8, 2013 at 4:05pm
Hi is an acid; KOH is a base. They partially neutralize each other. HI + KOH ==> KI + H2O You are right. Find the OH^-. mols HI = M x L = about 0.495 mols KOH = M x L = ? Subtract to find the one in excess and M = mols excess/total volume in L. Then pH = -log(H^+) if HI in ...
Sunday, December 8, 2013 at 1:37pm
The secret to these is to know where you are on the titration curve. First, find the equivalence points. There are three of them. Write the equation and balance it. Mols H3PO4 = M x L = ? mols KOH = mols H3PO4 that (look at the coefficients in the equation). mols KOH = M KOH/L...
Sunday, December 8, 2013 at 11:56am
Have you tried 0.510 + 0.510*(6/3) + 0.510*(5/3) =? This is the longer way of working it. Your 3/14(0.510) is on the right track but conceptually not quite right. Actually, Pdiatomic = 0.510 = (3/14)Ptotal And Ptotal = ? You should get about 2.4 atm either way but that 2.4 is ...
Sunday, December 8, 2013 at 10:54am
All of that looks good EXCEPT for using 0.026M for concentration of the propanoate ion. That is not 0.026 because it has been diluted by the addition of the NaOH. You started with 100 mL of 0.026M acid, when you've added 200 mL of NaOH the salt concn is now 0.026 x (100/...
Sunday, December 8, 2013 at 1:31am
I dislike chemistry sometimes.
Thursday, December 13, 2012 at 1:10am
b, d, e, a, c
Tuesday, April 17, 2012 at 10:27pm
is the answer 1,663,558.4 J
Monday, January 30, 2012 at 10:58am
Monday, May 16, 2011 at 9:54pm
3.55 x 10^-4 M
Tuesday, April 20, 2010 at 3:44pm