Zadania z chemii IB HL

When the equation for the complete combustion of 1 mol of pentan-1-ol, $\ce{C5H11OH}$, is balanced, what is the sum of all the coefficients? Unbalanced equation: $\ce{C5H11OH(l) + O2(g) -> CO2(g) + H2O(l)}$ A. 19 B. 19.5 C. 20 D. 39

The potential energy profile of a reaction is shown. Which reaction has this energy profile? A. $\ce{Cl2(g) -> 2Cl(g)}$ B. $\ce{CaCO3(s) -> CaO(s) + CO2(g)}$ C. $\ce{N2O4(g) -> 2NO2(g)}$ D. $\ce{2Mg(s) + O2(g) -> 2MgO(s)}$

The standard enthalpy changes of two reactions are given below. $\ce{N2(g) + O2(g) -> 2NO(g)}$ $\Delta H^\ominus = x\ \mathrm{kJ\,mol^{-1}}$ $\ce{2NO(g) + O2(g) -> 2NO2(g)}$ $\Delta H^\ominus = y\ \mathrm{kJ\,mol^{-1}}$ What is $\Delta H^\ominus$, in…

What is the enthalpy change, in $\mathrm{kJ\,mol^{-1}}$, for the formation of methanol from carbon monoxide and hydrogen? $\ce{CO(g) + 2H2(g) -> CH3OH(l)}$ Substance $\Delta H_\mathrm{c}^\ominus$ / $\mathrm{kJ\,mol^{-1}}$ $\ce{CO(g)}$ −283 $\ce{H2(g)}$ −286…

Which statement describes a disadvantage of using bioethanol rather than petrol (gasoline) as a fuel for cars? A. The carbon dioxide released when bioethanol burns was recently removed from the atmosphere by the crop B. Bioethanol releases less energy per…

Which equation represents the enthalpy change of atomization, $\Delta H_\mathrm{at}$, of iodine? A. $\ce{I2(s) -> I2(g)}$ B. $\ce{I2(g) -> 2I(g)}$ C. $\ce{1/2I2(g) -> I(g)}$ D. $\ce{1/2I2(s) -> I(g)}$

Which set of products can be formed by the incomplete combustion of butane, $\ce{C4H10}$? A. $\ce{C}$, $\ce{CO}$ and $\ce{H2O}$ B. $\ce{CO2}$ and $\ce{H2O}$ only C. $\ce{CO}$ and $\ce{H2}$ only D. $\ce{C}$ and $\ce{H2}$ only

Which statement best describes an environmental consequence of using fossil fuels? A. The carbon dioxide released is completely absorbed by the oceans, so its concentration in the atmosphere does not change. B. Coal has a higher hydrogen to carbon ratio than…