Calorimetry: Q = mcΔT and enthalpy change

In aqueous solution hydrogen cyanide behaves as a weak acid. (i) Write an equation for the ionization of hydrogen cyanide in water. (ii) Outline two ways in which a solution of 0.050 $\mathrm{mol\,dm^{-3}}$ $\ce{HCN}$ could be distinguished experimentally from…

Calculate the rise in temperature of 400.0 $\mathrm{cm^3}$ of water heated by the complete combustion of 2.00 g of butan-1-ol, assuming that all the energy released is transferred to the water. Use sections 2 and 14 of the data booklet.

A liquid fuel was burned in a spirit burner and the heat released was used to warm water in a metal calorimeter, as shown. Quantity Value Amount of fuel burned 0.0250 mol Mass of water 150 g Initial temperature of water 19.5 °C Final temperature of water 31.5…

When 0.601 g of propan-1-ol is burned, the heat released raises the temperature of 250 $\mathrm{cm^3}$ of water by 8.00 K. What is the enthalpy of combustion of propan-1-ol, in $\mathrm{kJ\,mol^{-1}}$, calculated from these results? Specific heat capacity of…

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…

Using sections 1 and 2 of the data booklet, determine the amount of heat that the water in beaker B gained from the metal.

Assume that the heat released by the metal is equal to the heat absorbed by the water in beaker B, calculated in 2a. Determine the specific heat capacity of the metal. Use section 1 of the data booklet. If you have no answer to 2a, take the heat transferred to…

Using the table below, state the name of the metal from which the block is made. Metal Specific heat capacity / $\mathrm{J\,g^{-1}\,K^{-1}}$ Tin 0.228 Zinc 0.388 Titanium 0.523 Magnesium 1.02

Deduce, from the results obtained, two sources of systematic error in this procedure.

(i) Suggest one hazard to health or safety in Student A's procedure. (ii) Student A plotted the highest temperature of each mixture against the volume of nitric acid. With a ruler, draw two straight lines of best fit: one following the rising set of points and…

Student B pipetted 30.00 $\mathrm{cm^3}$ of the potassium hydroxide solution into a 150 $\mathrm{cm^3}$ glass beaker and added the nitric acid from a burette in portions of 4.00 $\mathrm{cm^3}$, recording the steady temperature after each addition. Volume of…

The enthalpy of combustion of $\ce{C15H32}$ is $-10\,040\ \mathrm{kJ\,mol^{-1}}$. (i) Calculate the maximum amount of energy that the complete combustion of 1.75 g of pentadecane can release. (ii) The energy from burning the 1.75 g sample is used to heat…