Recent content by jibjab

This is where I'm completely lost. It looks to me like the tris base is acting as a base because it bonds with the Hydrogen on HCl. I guess this would make it more acidic afterward, so it would behave like a weak acid?

A proton donor/proton acceptor

After reviewing the other problems I worked, it looks like you multiply the acid or the base FW with the total buffer mol when one or the other is given in aqueous form? I don't understand why?

I understand that the acid is HCl and the conjugate base would be Tris-base, but what I don't understand is which method you use to determine the amount of base added to the buffer. For example, I've seen it solved one of two ways for different problems: 1) After solving for A, B would be...

Homework Statement To purify osprase you must use 750 mL of an extraction buffer consisting of 0.500 M Tris, pH 7.8, 100 mM NaCl, 20% sucrose. You have the following chemicals available: Tris base (FW = 121.1 g/mol; pKa = 8.1) 1.00 M HCl NaCl (FW = 58.4 g/mol) Sucrose (FW = 342 g/mol)...

OHH I was confusing antilog with natural log. I did say I was terrible at math. :blushing: Thanks for your help!

Homework Statement Prepare 750 mL of 0.5 M phosphate buffer, pH 6.7 and pKa 7.21. NaH2PO4 (119.96 g/mol) and Na2HPO4 (141.96 g/mol) is available to use. Homework Equations pH=pKa+log(B/A) The Attempt at a Solution I have the solution from my teacher, but I have no idea how he...

Homework Statement A 70.7 kg woman stands on a very light, rigid board that rests on a bathroom scale at each end. The total length of the board is L=2.1 m, and the woman's distance from the left of the board is 1.3 m. What is the reading on the left scale? The right scale? Homework...

Hi everyone, I am taking my first physics class ever and I'm lost! I have a couple of questions that are giving me a lot of trouble. Any assistance you can give me is very much appreciated! Homework Statement A turntable rotates counterclockwise at 85 rpm. A speck of dust on the turntable...

So simple and yet I couldn't get it! Thank you.

Homework Statement Part 1) The centers of a 21.2 kg lead ball and a 442 g lead ball are separated by 10.38 cm. What gravitational force does each exert on the other? Part 2) What is the ratio of this gravitational force to the weight of the 442 g ball? The Attempt at a Solution I...

Ah thank you!

Homework Statement A skater holds her arms outstretched as she spins at 225 rpm. What is the speed of her hands if they are 152 cm apart? The Attempt at a Solution I converted 225 rpm to 3.57 rps and found the angular velocity (23.56 rad/s) to plug into the equation v=wr, but it didn't...