Zadania z chemii IB HL

The average times were plotted against concentration. Draw a curve of best fit through the points on the graph.

A second student repeated the experiment with the same five solutions and the same apparatus and obtained the following times. Concentration of $\ce{Na2S2O3}$ / $\mathrm{mol\,dm^{-3}}$ Reaction time / s (± 0.1 s) 0.2000 ± 0.08 % 20.1 0.1000 ± 0.2 % 37.5 0.0500…

The rate of the reaction can be followed by measuring the volume of carbon dioxide collected as time passes. The graph shows the results obtained at 20 °C. (i) Sketch, on the same axes, the curve you would expect if the experiment were repeated with the acid…

Explain, using collision theory, why the rate of this reaction decreases when the temperature is lowered.

Which changes increase the rate of the reaction? $\ce{CaCO3(s) + 2HCl(aq) -> CaCl2(aq) + H2O(l) + CO2(g)}$ I. Grinding the calcium carbonate into a fine powder II. Using a larger volume of hydrochloric acid of the same concentration III. Warming the…

(i) Sketch the Maxwell–Boltzmann energy distribution curve for the particles in this reaction mixture at 25 °C, marking on the diagram the activation energy both with and without the catalyst. (ii) On the same axes, sketch and label a second Maxwell–Boltzmann…

(i) Sketch the Maxwell–Boltzmann distribution curve for 298 K on the same axes as the 800 K curve. (ii) On the graph, annotate the position corresponding to the activation energy, $E_\mathrm{a}$. (iii) With reference to the graph, explain why a lower…

The dotted line shows the volume of hydrogen produced when an excess of magnesium ribbon is added to 50 $\mathrm{cm^3}$ of 2.0 $\mathrm{mol\,dm^{-3}}$ hydrochloric acid. Which curve shows the volume of hydrogen produced when the same excess of magnesium ribbon…

Raising the temperature of a reaction mixture by 10 °C can double the rate of reaction, even though the collision frequency increases by only a few per cent. What is the main reason for the large increase in rate? A. The activation energy of the reaction is…