Tuesday
May 21, 2013

Posts by Sam


Total # Posts: 3341

Analytical Chemistry
Show the predominant form of the amino acid tyrosine at pH=13.9 and ph=7.8. Be sure to include the proper number of hydrogens on heteroatoms and the correct formal charges on atoms. I calculated the pka values for COOH (pka=2.41) NH3 (pka=8.67), and OH (pka=11.01) but i'm...

Analytical Chemistry
You prepare a solution from 10.0 mL of 0.100 M MOPS buffer (3-morpholinopropane-1-sulfonic acid) and 10.0 mL of 0.086 M NaOH. Next, you add 1.00 mL of 8.87 × 10-4 M lidocaine to this mixture Denoting lidocaine as L, calculate the fraction of lidocaine present in the form...

Analytical Chemistry
I got the answer, thanks!

Analytical Chemistry
What fraction of piperazine (perhydro-1,4-diazine) is in each of its three forms (H2A, HA–, A2–) at pH 7.05? Not sure how to find k1 and k2 needed for the fraction formulas...please help :(

Literature
Repeated words, papragrapgh transition, conjunction sentences etc. Just want to make sure on my writing. I am in seventh grade. I don't want to copy and paste it on here in case other kids might use my writing. Other wise I would ask you to look at it. I wish.

Literature
Hi where can I find a free on line thing to check my writing ?

physics
Two spherical shells have a common center. A -2.00 × 10-6 C charge is spread uniformly over the inner shell, which has a radius of 0.050 m. A +5.50 × 10-6 C charge is spread uniformly over the outer shell, which has a radius of 0.15 m.

Math
Find the equation of the secant line to the graph of y= 2x^3-3x^2+4x-1 from x=1 to x=3. Give your answer in slope-intercept form.

Analytical Chemistry
Phosphoric acid is a triprotic acid with the following pKa values: pka1: 2.148 pka2: 7.198 pka3: 12.375 You wish to prepare 1.000 L of a 0.0100 M phosphate buffer at pH 7.45. To do this, you choose to use mix the two salt forms involved in the second ionization, NaH2PO4 and Na...

Analytical Chemistry
Yes I have online homework which I use to submit my homework on. I calculated H2CO3 and got the same value as yours. then I solved for x and got 2.3 x 10^-6 M. Finally i plugged it into the ph formula to get a ph of 5.64. Thank you so much! It was correct!

Pages: <<Prev | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | Next>>

For Further Reading

Search
Members
Community