Question

The composition of 1X TBE is: 89mM Tris (molar mass = 121.14 g/mol) 89mM Boric Acid...

The composition of 1X TBE is: 89mM Tris (molar mass = 121.14 g/mol) 89mM Boric Acid (molar mass = 61.83 g/mol) 2mM EDTA (molar mass = 292.24 g/mol) However, TBE is commonly made as a concentration 10x buffer that is then diluted to 1X just prior to use.

1) What are the concentrations each of the components in the 10X TBE storage buffer? Tris:______________ Boric Acid:_________ EDTA:____________

2) Now calculate the amount of each components in grams needed to make 1L of th 10x TBE storage buffer. For full credit, show all of your work.

Homework Answers

Answer #1

The composition 1X TBE buffer is: 89mM Tris (Molar mass = 121.14 g/mol) 89mM Boric acid (molar mass = 61.83 g/mol) 2mM EDTA (Molar mass = 292.24 g/mol)

1. The concentration of 1X TBE can be multiplied by 10 to arrive at 10X concentration. So molar concentrations are also multiplied by 10.

So, concentrations of each of the components in the 10X TBE buffer are:

Tris : 890mM = 0.890M

Boric acid : 890mM = 0.890M

EDTA : 20mM = 0.020M

2. To calculate the amount of each of the components in grams, multiply the molar concentrations with the respective molar masses. As these are molar concentrations, the calculated amount in grams will be for 1L of buffer solution.

Thus, Tris: 0.890 mol/L * 121.14 g/mol = 107.8 g 108 g

Boric acid : 0.890 mol/L * 61.83 g/mol = 55 g

EDTA : 0.020 mol/L * 292.24 g/mol = 5.84g 6 g

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
TAE is a commonly used buffer for DNA el ectrophoresis. This buffer contains 40 mM Tris,...
TAE is a commonly used buffer for DNA el ectrophoresis. This buffer contains 40 mM Tris, 20 mM Acetate, 1 mM EDTA as the final concentrations. A 50X stock solution (50X the final concentration) is normally prepared. You have Tris powder (mol. wt. 121.14), glacial acetate acid (a liquid with a density of 1.05 g/mL and a mol. wt. of 60) and 0.5 M EDTA stock solution. You need to make up 1 Li ter of 50X TAE. How would...
A compound has a molar mass of 180.1 g/mol and has the following composition by mass:...
A compound has a molar mass of 180.1 g/mol and has the following composition by mass: C = 40.0%; H = 6.70 %; O = 53.3%. Determine the empirical formula, the empirical formula molar mass, and the molecular formula of the compound.
The buffer bis-Tris is a commonly used in biochemistry labs. It has a Ka = 3.16...
The buffer bis-Tris is a commonly used in biochemistry labs. It has a Ka = 3.16 x 10-7 and a molar mass of 209.2 g/mol. Show all of your calculations clearly and with correct units and reasonable significant figures. The small x approximation may be used throughout. a) How many grams of bis-Tris are needed to make 1-L of a 0.100 M solution? b) What is the pKa of bis-Tris? c) What is the pH of the 0.100M solution of...
When 2.50 g of an unknown weak acid (HA) with a molar mass of 85.0 g/mol...
When 2.50 g of an unknown weak acid (HA) with a molar mass of 85.0 g/mol is dissolved in 250.0 g of water, the freezing point of the resulting solution is -0.259 ∘C. Calculate Ka for the unknown weak acid.
You titrate a 20.0 mL acid sample containing 1.104 g of ascorbic acid (molar mass=176.12 g/mol...
You titrate a 20.0 mL acid sample containing 1.104 g of ascorbic acid (molar mass=176.12 g/mol and pKa=4.10) with 0.200 M NaOH. Calculate the following 1. The pH at the begining of the titration, before any base was added 2. The volume of base (NaOH) required to reach the equivalence point 3. The pH at the equivalence point and the half-equivalence point 4. The pH after 35.5 mL of base have beedn added