Daily NEET MCQ- June 18, 2022 - NEET MCQ

An acidic buffer has a pH value of less than 7, Acetic Acid-Sodium Acetate and boric acid-borax are examples of acidic buffers, but ammonium Hydroxide-ammonium chloride has a pH of greater than 7, so they are basic buffers.

If the addition of a strong acid or base changes the pH of a buffer by unit, the buffer solution is assumed to be destroyed that is new pH = pK_a ± 1; that means [salt]/[acid] or [acid]/[salt] = 10 or 1/10.

Buffer capacity is defined as the number of moles of acid or base added in one litre of the solution to change the pH by Unity. Therefore here buffer capacity = 3/5 divided by 2 = 0.6/2 = 0.3. The buffer capacity is given as 0.3.

Moment of inertia is the summation of product of mass and perpendicular distance from the axis squared of each particle. More the mass, more will be its value. It depends on perpendicular distance hence, it will depend on orientation and distance of particles from the axis. But, it doesn’t depend on the angular velocity. As the body having a particular value of moment of inertia can achieve any value of angular velocity depending on the torque applied on it.

The hollow one will have greater density as both have the same mass and it has to be distributed uniformly. Thus, the summation of product of mass and perpendicular distance from the axis squared of each particle will be more for the hollow cylinder. And hence, it has more moment of inertia.

Moment of inertia of disc = MR²/2 = 10*1/2 = 5kgm².
Radius of gyration ‘k’ is given by the expression: I = Mk²
∴ k = √(I/M)
= √(5/10) = 0.707m.

The molecular weight of biomacromolecules such as nucleic acids, proteins and carbohydrates is measured in Daltons. Angstrom and nanometer are units of length while farad is a unit of capacitance.

The acid insoluble pool or fraction of the homogenized plant or animal tissue contains proteins, lipids, carbohydrates and nucleic acids. These molecules are also known as biomolecules. Vitamins are not present.

The acid insoluble layer of homogenized, strained tissue consists of proteins, nucleic acids, lipids and polysaccharides. Out of these biomacromolecules, lipids have a molecular weight lesser than 10,000 Da.

When tissue matter is homogenized and strained, it separates into an acid soluble pool and an acid insoluble pool. The acid insoluble pool contains proteins, nucleic acids, polysaccharides and lipids. Out of these, only lipids are not polymeric.