Question 1:
A solution needs 250 ml of a 7.5% (w/v) solution of tri sodium citrate. The only citrate you encompass available is the dehydrate, C6H5O7Na3. 2H20 through a formula weight of 294.1.How much would you encompass to make up this solution?
Question 2:
A citrate buffer should be made up to a final concentration of 50mM. You require making up 2L. You have to stock solutions from which to make this buffer; 0.1 M citric acid (C6H8O7) and 0.1 M Sodium citrate (C6H5O7Na3). You require adding twice as much of the acid form than the base form to accomplish the desired pH. Illustrate how will you make up this solution?
Question 3:
To isolate RNA you frequently use a protein denaturant solution of guanidinum salts. Such chaotropic solutions denature through disrupting H-bonding. The solution also contains a reducing agent to denature the disulfide bonds. The final composition of the solution is: 4 guanidine isthiocyanate (GITC), 25mM sodium citrate, pH 7.0, 0.5% (w/v) SDS, 100mM β-mercaptoethanol. You have guanidine isothiocyanate powder (mol.Wt.118.16),1 M NaCitrate, pH 7.0, powder SDS and b-mercaptoethanol (density 1.12 g/mL, mol. Wt.78.1). How would you build up 100 mL of this solution?