Zadania z chemii IB HL

Which of the following could be used to follow the progress of the reaction between calcium carbonate and dilute nitric acid? $\ce{CaCO3(s) + 2HNO3(aq) -> Ca(NO3)2(aq) + H2O(l) + CO2(g)}$ I. A balance recording the mass of the open flask and its contents II. A…

30 $\mathrm{cm^3}$ of butane was completely burned in 250 $\mathrm{cm^3}$ of oxygen according to the following equation. $\ce{2C4H10(g) + 13O2(g) -> 8CO2(g) + 10H2O(l)}$ What volume of oxygen remains unreacted, measured at the original conditions? A. 55…

The rate of the reaction between propanone and iodine in acidic solution was measured at a fixed concentration of the acid catalyst. $\ce{CH3COCH3(aq) + I2(aq) -> CH3COCH2I(aq) + HI(aq)}$ $[\ce{CH3COCH3}]$ / $\mathrm{mol\,dm^{-3}}$ $[\ce{I2}]$ /…

The table shows how the initial rate of the reaction between X and Y depends on the concentrations of the reactants. Experiment $[\ce{X}]$ / $\mathrm{mol\,dm^{-3}}$ $[\ce{Y}]$ / $\mathrm{mol\,dm^{-3}}$ Initial rate / $\mathrm{mol\,dm^{-3}\,s^{-1}}$ 1 0.10 0.20…

The Maxwell–Boltzmann distribution below was obtained for a sample of gas at temperature $T_1$. The activation energy of a reaction is marked as $E_\mathrm{a}$. Which graph shows the distribution for the same sample at a higher temperature, $T_2$, together…

Which statement about the rate constant, k, of an elementary reaction is correct? A. k increases when the temperature is raised, whether the reaction is exothermic or endothermic. B. k decreases when the temperature is raised for exothermic reactions. C. k…

A reaction has the rate equation below. What are the units of the rate constant $k$? rate $= k[\ce{A}]^2[\ce{B}][\ce{C}]^0$ A. $\mathrm{s^{-1}}$ B. $\mathrm{mol^{-1}\,dm^{3}\,s^{-1}}$ C. $\mathrm{mol^{-2}\,dm^{6}\,s^{-1}}$ D.…

The gas-phase decomposition below has reached equilibrium in a sealed vessel: $\ce{PCl5(g) <=> PCl3(g) + Cl2(g)}$ $\Delta H^\ominus = +88\ \mathrm{kJ\,mol^{-1}}$ The pressure is then changed. Which row pairs the change correctly with the direction in which the…

The following system is at equilibrium. $\ce{H2(g) + I2(g) <=> 2HI(g)}$ $K = 54$ What is the value of the equilibrium constant, K, for the reaction $\ce{2HI(g) <=> H2(g) + I2(g)}$? A. $-54$ B. $\dfrac{1}{54}$ C. $\sqrt{54}$ D. $\dfrac{1}{\sqrt{54}}$