Tris hydroxyethyl aminoethane (THAE) has a pk, of 8.4. The buffering capacity of a buffer made with this compound will be greatest at which pH? (1) pH 9.4 ffer (2) pH 7.4 (3) pH 8.4 (4) Both at pH 7.4 and 9.4 Concept: Buffering Capacity and pKa The buffering capacity of a buffer is highest … Read more
What is the concentration of OH in a solution with a H’ concentration of 1.3 * 10 ^ – 4 M? (1) 7.7 * 10 ^ – 10 * M (2) 7.7 * 10 ^ – 9 * M (3) 7.7 * 10 ^ – 11 * M (4) 7.7 * 10 ^ – 12 … Read more
A 10 N HCI solution was diluted 10-fold with water and the pH of the diluted solution was measured with a pH meter after calibration using standard solutions. Given that the activity coefficient for diluted HCI was 0.01, the pH of the solution would be (1) 0 (3) 2 (2) 1 (4) 2.5
Which one of the following amino-containing buffering molecules will be the most able to resist change in pH when in a pH 7.0 solution at a total (ionized and non-ionic) concentration of 100mM? (1) Tris (pKa = 8.1) (3) MOPS {pKa = 7.3} (2) HEPES (pKa = 7.7) (4) PIPES (pKa = 7.1) Concept: Best … Read more
If the intracellular pH of a cell becomes basic, which one of the following will help reduce the pH? (1) Export of Cl and import of HCO (2) Import of Cl and export of HCO (3) Import of Na” and HCO3- and export of Cl (4) Export of Na’ and Cl If the intracellular pH … Read more
If you were to take 1.0 ml of a solution of HCl with a pH of 4.0 and add it to 9.0 ml of distilled water, what would be the pH of the final solution? (1) The pH would remain unchanged. (2) The pH would rise to 5.5. (3) The pH would rise to 5.0. … Read more
How many millilitres of 0.05 N HCI are required to neutralize eight grams of NaOH? (1) 5000 (2) 4000 (3) 4500 (4) 5050 To determine the volume of 0.05 N HCl required to neutralize 8 g of NaOH, follow these steps: Step 1: Calculate Moles of NaOH Molecular weight of NaOH = 40 g/mol Moles … Read more
Among the following bonds where rotation is not allowed in a peptide chains? (1) ψ (2) ω (3) x (4) φ In a peptide chain, rotation is restricted due to partial double-bond character of certain bonds. Let’s analyze each option: 1. ψ (Psi) angle – Rotation Allowed 
This is the Cα–C bond (between the … Read more
Arrange the three residues, glycine, phenylalanine and proline, in the decreasing order of backbone flexibility (1) Gly > Phe > Pro (2) Pro > Gly > Phe (3) Phe > Pro > Gly (4) It is not possible to comment Backbone flexibility in amino acids depends on the torsional freedom of the main chain (Φ, … Read more
In a polypeptide chain, a cis-to-trans rearrangement of two consecutive proline residues can be achieved by rotating the: (1) O angle to 10° (2) w angle to 180° (3) Ψ angle to 0° (4) x angle to 60° In a polypeptide chain, cis-to-trans isomerization primarily involves rotation around the peptide bond (ω angle). ω (omega) … Read more