1. Usain Bolt used 850 kcal on a long walk. Calculate the energy he used for the walk in the following units: (a) Joules
(b) Kilojoules
2. A high-protein diet contains 72.0-g of carbohydrate, 6.0-g of fat, and 160-g of protein. How much energy, in kilocalories, does the diet provide (round to the nearest tens place).
3. How many kilocalories are lost when 580-g of water cools from 67oC to 22oC?
4. In a freezer, 160-g of water at 0oC is placed in an ice cube tray. How much heat, in kilocalories, must be removed to form ice cubes at 0oC?

cc jyfu65   6r 67r   r576dyfu r6tyuio fghjkl;

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

hypostyle hall;