Wednesday

October 7, 2015
Total # Posts: 24

**Urgent Chemistry**

The diffusion current for a standard is 1 x 10^-4M solution of hydroquinone is 17.5 microamperes. An unknown solution of hydroquinone, when diluted hundred folds and polarographed under same conditions yielded a current of 30.5 microamperes. Calculate the concentration of ...
*August 4, 2015*

**chemistry**

Zinc is to be used as an internal standard for the polarographic analysis of thallium. A standard solution containing twice the concentration of zinc as thallium has diffusion currents of 1.89 microAmps for thallium and 3.5 microAmps for zinc. A 10.0g sample of an alloy ...
*July 10, 2015*

**chemistry**

The polarogram for 20ml solution that was 3.65 x 10^-3 M in cadmium (Cd2+) gave a wave for that ion with a diffusion current of 31.3microampere. Calculate the percentage change in concentration of the solution is the current in the limiting current region were allowed to ...
*July 10, 2015*

**chemistry**

Thanks for d reply. Pls if i want to calculate for a pH less than 7 (eg 5.8), wil i subtract d volume i obtain from 30ml or will i add it?
*March 21, 2015*

**chemistry**

Calculate the volume of NaOH 0.1M that needs to be calculated to be added to a 30ml o-phosphoric acid 0.1 in order to prepare solutions of pH 7.5 and pH 6.9? pKa3= 2.15; pKa2=7.2; pKa1 = 12.1
*March 21, 2015*

**chemistry**

explain how to prepare a 200cm,0.25 ofH2SO4
*August 24, 2014*

**math**

x is partly constant and partly varies as y, when y=2,x=0 and when y=6,x=20.find x when y=3
*January 15, 2014*

**Math**

Solve the following equation 1) root(2x+4)= root(6x+1) -1
*August 24, 2010*

**Math**

(root2 + root3)^2 simplify
*July 1, 2010*

**Math**

How can i factor 27a^2 - 75b^2
*July 1, 2010*

**Calculus**

A tool shed, 250cm high and 100cm deep, is built agaisnt a wall. Calculate the shortest ladder that can reach from the ground, over the shed, tot he wall behind.
*June 20, 2010*

**Calculus**

A travel agency currently has 80plp signed up a tour. The price of a ticket is $5000 per person. The agency has chatered a plane seating 150 plp at a cost of $250000. Additional costs to the agency are incidental fees of $300 per person. For each $30 that the price is loverwd...
*June 19, 2010*

**Calculus**

A cylindrical metal can is made to hold 500ml of soup. Determine the dimensions of the can that will minimize the amount of metal required(assume that the top and sides of the can are made from metal of the same thickness
*June 18, 2010*

**Calculus**

The position at time t, in seconds of an object moving along a like is s(t)= 3r^3 - 40.5t^2 + 162t fot 0<= t <=8 When is the obkjection advancing anf whne is it retreating
*June 18, 2010*

**chemistry**

When 25ml of 0.10 mol/l HBr is titrated with 0.10 mol/l NaOH, what is the pH at the equivalence point?
*June 15, 2010*

**Chemistry**

Predict whether the following solutions are acidic basic or neutral. Provide explanations to support your predictions a) ammonium phosphate b) Ammonium sulfate c) Magnesium oxide
*June 14, 2010*

**Chemistry**

One mole methane is completly burned in xcess oxygen. If 8.90x10^3kj of heat are given off from theis reaction, calculate the heat given off for 1.44g of methane.
*June 14, 2010*

**Chemistry**

Balance the ewuation using thr oxidation number method Here is what i did Au+ + H20---> Au2O3 + Au + H+ Au+ losses 3e- to form Au2O3-->oxidation Au+ gets reduced to for Au therefore the balanced chemical equation is 3Au+ + 3H20---> Au2O3 +Au +6H+ Does it make sense?
*June 13, 2010*

**Chemistry**

Predict whether the Ph endpoint is =7 >7, or<7 for each of the following acid-base titrations. Justify you predictions a) hydroiodic acid with sodium hydroxide. b)boric acid with sodium hydroxide c) hydrochloric acid with magnesium hydroxide d) hydrochloric acid with ...
*June 13, 2010*

**vectors**

What is the cartesian equation of the xz plane
*June 9, 2010*

**English**

Thank you Ms. Sue for pointing out that huge mistake i made. Other than that is the intro well written? I changed it up abit What makes a book good to read? Is it the fact that information is gotten out of it or just the mere enjoyment of being able to use our imagination to ...
*June 5, 2010*

**English**

Can someone please read the intro to my essay and tell me if it makese sense? The topic of the essay is to see whether nonfiction novels can equal or surpass fiction novels. THE BATTLE OF BOOKS: FICTION VS. NONFICTION What makes a book good to read? Is it the fact that ...
*June 5, 2010*

**English**

Is it possible to say that the main reason that Shakespeare wrote many of his plays is to entertain the people of the Elizabethian era.
*June 5, 2010*

**Calculus**

The hypotenuse od a right triangle is 12cm in lenht. Calculate the measures of the unknown angle in the triangle that will maximize its perimeter? I got the formula P= 12(1 + sin0 + cos0) and A= 12sin0cos0, but i dont know what to do next.
*April 10, 2010*

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