Zadania z chemii IB SL

A student stirred 0.030 mol of solid sodium hydrogencarbonate into 40 $\mathrm{cm^3}$ of a 1.0 $\mathrm{mol\,dm^{-3}}$ solution of ethanedioic acid. $\ce{H2C2O4(aq) + 2NaHCO3(s) -> Na2C2O4(aq) + 2CO2(g) + 2H2O(l)}$ The temperature of the solution fell from…

Which are units for rate of reaction? A. $\mathrm{s\,mol^{-1}\,dm^{3}}$ B. $\mathrm{mol\,dm^{-3}\,min}$ C. $\mathrm{mol\,dm^{-3}\,min^{-1}}$ D. $\mathrm{mol\,min^{-1}}$

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…

One route to 2-bromopropane is the substitution of propane by bromine in ultraviolet light. $\ce{C3H8(g) + Br2(g) -> C3H7Br(g) + HBr(g)}$ ($\ce{C3H8}$ = 44.11 $\mathrm{g\,mol^{-1}}$, $\ce{Br2}$ = 159.80 $\mathrm{g\,mol^{-1}}$, $\ce{C3H7Br}$ = 123.00…

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…

Iron(III) ions and thiocyanate ions form a deep red complex ion in aqueous solution. $\ce{Fe^3+(aq) + SCN^-(aq) <=> [Fe(SCN)]^2+(aq)}$ Which of the following correctly predicts the effect of a change on this equilibrium? A. Adding iron(III) nitrate solution…

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…

Increasing the temperature of a reaction mixture increases the rate of reaction. What is the best explanation for this? A. A greater proportion of collisions occur with energy greater than or equal to the activation energy. B. A greater proportion of…

What amount of oxygen, in mol, is required to burn 8.72 g of butane, $\ce{C4H10(g)}$, completely? $M$(butane) = 58.14 $\mathrm{g\,mol^{-1}}$ A. 0.0231 B. 0.150 C. 0.975 D. 1.95