Effectively, how many valence electrons are there in each atom within q silicon crystal?​

Different types of steels contain different elements that alter the characteristics of the steel. for each of the following elements, explain what the element does when alloyed with steel.

Carbon dioxide gas expands isotherm a turbine from 1 mpa, 500 k at 200 kpa. assuming the ideal gas model and neglecting the kinetic and potential energies, determine the change in entropy, heat transfer and work for each kilogram of co2.

How to increase the thermal officiency of an ideal simple rankino cycle? among these methods, which one is the best and why?