What is the change in enthalpy of the first reaction below, given the enthalpies of the other two reactions?

In this reaction n2o4(g)→2no2(g) what changes in color would you expect as pressure is increased at a constant temperature

How can a give a full method for the experiment of separating sand from water by filtration? 1-materials 2-steps 3-conclusion also for water and salt separated by the evaporation or distillation process

At element makes up all organic compounds?