DP Chemistry (first assessment 2025)
Question 19M.1A.HL.TZ2.21
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.1A.HL.TZ2.21 |
| Level | HL | Paper | 1A | Time zone | TZ2 |
| Command term | Question number | 21 | Adapted from | N/A |
21.
[Maximum mark: 1]
19M.1A.HL.TZ2.21
What is the order with respect to each reactant?
2NO (g) + Cl2 (g) → 2NOCl (g)
[1]
Markscheme
C
Examiners report
88 % of the candidates deduced the order of the reaction with respect to each reactant based on the experimental data of initial rate and concentrations of reactants.
Syllabus sections
Reactivity 2. How much, how fast and how far? » Reactivity 2.2—How fast? The rate of chemical change » Reactivity 2.2.10—The order of a reaction with respect to a reactant is the exponent to which the concentration of the reactant is raised in the rate equation. The order with respect to a reactant can describe the number of particles taking part in the rate determining step. The overall reaction order is the sum of the orders with respect to each reactant. Sketch, identify and analyse graphical representations of zero, first and second order reactions.