NEET Test 45

Respiratory quotient RQ) is the ratio of carbon dioxide output to oxygen usage during respiration. High RQ values occur in conditions such as fat deposition, fever, muscle exercise, glycolysis etc. Low RQ is found in acidosis, alkalosis, diabetes, starvation, etc.

The cranial nerves consist of all three types of nerves, i.e., motor, sensory and mixed nerves. Each spinal nerve is a mixed nerve composed of both sensory and motor neurons.

Rigidity that develops in the muscle after death is termed as rigor mortis. It is due to permanent irreversible concentration, establishment of permanent link between actin and myosin and also falls in the concentration of ATP molecules.

sciatic plexus is formed by 7^th, 8^th and 9^th spinal nerves in frog.

Sir J.J. Thomson, observed that when a light of certain frequency strikes the surface of a metal, electrons are ejected from the metal. This phenomenon is known as photoelectric effect and the ejected electrons are called photoelectrons.

The dissociation of NaCl in water can be represented as: 

NaCl → Na⁺ + Cl^- 

H₂O →H⁺ + OH^- 

When Pt electrode is used: 

At cathode: 

H⁺ + e^- → H 

H + H → H₂ 

At anode: 

Cl^- + e^-→ Cl 

Cl + Cl → Cl₂ 

When Hg is used as cathode: 

Due to high hydrogen over voltage of Hg, Na⁺ ions are discharged at cathode in preference to H⁺ ions which gives sodium amalgam after Na dissolves in Hg.

Oxidation number of K = +1

oxidation number of O = -2

Let the oxidation number of Cr =X

So

+1(2) + X(2) + ─2(7) = 0

2 + X(2) ─ 14 = 0

─12 + X(2) = 0

2X = 12

X=6 

So the oxidation number of Cr in K₂Cr₂O₇ is +6