You have a mixture that contains 10 g of Mo-93 with a half-life of
3.5 x 103
years and 10 g of
Ca-47 with a half-life of 4.5 days. Estimate how much time must elapse before the quantity of radioactive material is
reduced by 50% by mass.

answer: the value of enthalpy change will be -152.80 kj.

solution:

pressure = 1atm , temperature = = 298 k

given that pressure and temperature are same in both gases , the number of moles of both gases can be determined by the ideal gas equation.

according to reaction 3 moles no are reacting with 1 mol of ,then 0.49 mol of no will react with moles of ozone that is 0.16 moles of ozone. since, no is limiting reagent and is an excessive reagent.

enthalpy change for the reaction between the given volumes of the gases is :

it forms an anion that has a larger radius. anions have a negative charge and are larger than the original atom.