While making 100 ml of 2M NaCl solution, a student left the solution on a heating platform reducing the volume by 50 ml. This solution was diluted 1:100 for use. What is the final concentration of NaCl in this solution? (1) 20 mM (3) 40 mM (2) 80 mM (4) 400 mM
Two solutions of a substance (non-electrolyte) are mixed in the following manner: 480 ml of 1.5 M first solution+ 520 ml of 1.2 M second solution. What is the molarity (M) of the final mixture? (1) 1.250 (3) 1.433 (2) 1.344 (4) 1.479
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 5 ml of 20% ethanol is mixed with 25 ml of 80% ethanol, the resulting solution will approximately be (1) 50% ethanol (3) 100% ethanol (2) 70% ethanol (4) 80% ethanol
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
What will be the required volumes of 1N HCl and 4N NaOH to prepare one litre solution of pH 77 (1) 500 ml, 500 ml. (3) 600 ml, 400 ml (2) 800 ml, 200 ml (4) 200 ml, 800 ml To prepare 1 litre of a solution with pH = 7 using 1N HCl and … 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