Chemical Bonding and Molecular Structure — Chemistry STD 11 Science — Question

1. An athlete is given 100g of glucose of energy equivalent to 1560kJ. He utilises 50% of this gained energy in the event. In order to avoid storage of energy in the body, calculate the weight of water that would need to perspire. The enthalpy of vaporisation of water is 44kJ mol^-1.
2. Compound with carbon-carbon double bond, such as ethylene, C₂H₄, add hydrogen in a reaction called hydrogenation, C₂H₄(g) + H₂(g) → C₂H₆(g)

Calculate enthalpy change for the reaction, using the following combustion data,

$\text{C}_2\text{H}_4(\text{g})+3\text{O}_2(\text{g})\overrightarrow{\ \ \ \ \ }\ 2\text{CO}_2(\text{g})+2\text{H}_2\text{O(l)};$ $\Delta_\text{c}\text{H}^\circ=-1401\text{kJ mol}^{-1}\dots(\text{i})$

$\text{C}_2\text{H}_6(\text{g})+\frac{7}{2}\text{O}_2(\text{g})\overrightarrow{ \ \ \ \ \ \ \ }\ 2\text{CO}_2(\text{g})+3\text{H}_2\text{O(l)}$ $\Delta_\text{c}\text{H}^\circ=-1550\text{kJ mol}^{-1}\dots(\text{ii})$

$\text{H}_2(\text{g})+\frac{1}{2}\text{O}_2(\text{g})\overrightarrow{ \ \ \ \ }\ \text{H}_2\text{O(l)};$ $\Delta_\text{c}\text{H}^\circ=-286.0\text{kJ mol}^{-1}\dots(\text{iii})$

1. Radius of zinc atom in pm
2. Number of atoms present in a length of 1.6cm if the zinc atoms are arranged side by side lengthwise.