Both Pozzolans and hydraulic cements are categories of supplementary cementitious materials. The difference between them is that pozzolans react directly with water to form a cementitious compound whereas hydraulic cements react with the calcium hydroxide in wet concrete to form cementitious compounds. Group of answer choices

Ahe-xe mixture containing a 0.75 mole fraction of helium is used for cooling electronics in an avionics application. at a temperature of 300 k and atmospheric pressure, calculate the mass fraction of helium and the mass density, molar concentration and molecular weight of the mixture. if the cooling capacity is 10 l, what is the mass of the coolant?