Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Advanced2006ChemistryChemical KineticsActual

Paragraph: Carbon-14 is used to determine the age of organic material. The procedure is based on the formation of ¹⁴ C by neutron capture in the upper atmosphere. ₇¹⁴ ~N + ₀^1 n ₆¹⁴ C + ₁ n^1 ¹⁴ C is absorbed by living organisms during photosynthesis. The ¹⁴ C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of ¹⁴ C in the dead being, falls

Options

  1. AIn living organisms, circulation of ¹⁴ C from atmosphere is high so the carbon content is constant in organism
  2. BCarbon dating can be used to find out the age of earth crust and rocks.
  3. CRadioactive absorption due to cosmic radiation is equal to the rate of radioactive decay, hence the carbon con
  4. DCarbon dating can not be used to determine concentration of ¹⁴ C in dead beings.

Correct answer

C. Radioactive absorption due to cosmic radiation is equal to the rate of radioactive decay, hence the carbon con

Step-by-step solution

Radioactive absorption due to cosmic radiation is equal to the rate of radioactive decay, hence the carbon content as the ratio of C ¹⁴ to C ¹² remains constant in living organism.

Practice Chemical Kinetics on Quantrex Academy →

More from Chemical Kinetics

For a reversible reaction R P , at constant temperature, both the forward and the backward reactions are first order elementary reactions with rate constants k_f and k_b , respecti 2026For a first-order reaction R P at a given temperature, k is the rate constant. For this reaction, at the given temperature, the concentrations of R and P at a time t are [ R ] and 2026Given below are two statements: R=8.314 J K ⁻¹ mol ⁻¹ and 1 cal =4.2 J Statement I: When E_a=12.6 kcal/mol, the room temperature rate constant is doubled by a 10 ,^ C increase in t 2026Decomposition of a hydrocarbon follows the equation k = (5.5 10¹¹ , s ⁻¹) ,e^ -28000 , K T . The activation energy of reaction is __________ kJ mol ⁻¹ . (Nearest Integer) Given : R 2026For a reaction A P at T K , the half life (t_ 1/2 ) is plotted as a function of initial concentration [A]₀ of A as given below. The value of x in the given figure is _______ s (Nea 2026First order gas phase reaction A B + C p_i = initial pressure of gas A, p_t = total pressure of the reaction mixture at time t Expression of rate constant ( k ) is 2026If the half life of a first order reaction is 6.93 minutes then the time required for completion of 99 % of the reaction will be _____ minutes. (Given : 2 = 0.3010 ) 2026Consider the given graph showing variation of reactant concentration with time. Three different reactions were started with identical initial concentration of reactants. Which of t 2026 Full Chemical Kinetics list All JEE Advanced PYQs