For a given reaction, the activation energy is 63.9 kJ/mol. If the reaction rate constant is 4.1 x 10^–3 M^–1 s^–1 at 32.0 °C, what is the reaction rate constant at –5.0 °C? (R = 8.314 J/K·mol)

1. suppose a reaction mixture, when diluted with water, afforded 300 ml of an aqueous solution of 30 g of the reaction product malononitrile [ch2(cn)2], which is to be isolated by extraction with ether. the solubility of malononitrile in ether at room temperature is 20.0 g/100 ml, and in water is 13.3 g/100 ml. what weight of malononitrile would be recovered by extraction with (a) three 100-ml portions of ether and (b) one 300-ml portion of ether? suggestion: for each extraction, let x equal the weight extracted into the ether layer. in part (a), the concentration in the ether layer is x/100 and in the water layer is (30 x)/300; the ratio of these quantities is equal to k 20/13.3.

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Which change to the system wood cause the freely-moving piston to lower?