There is evidence that liquid water existed on Mars at some time in the past. What is the evidence found indicating the presence of liquid water? Why isn’t it possible to have liquid water on the surface today?

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

Heat is added to a piston-cylinder device filled with 2 kg of air to raise its temperature 400 c from an initial temperature of t1 27 cand pressure of pi 1 mpa. the process is isobaric process. find a)-the final pressure p2 b)-the heat transfer to the air.

Describe one experiment in which the glass transition temperature and melting temperature of a totally amorphous thermoplastic material can be determined. show the relevant experimental results in a diagram which should be properly annotated with the two temperatures clearly marked. what is likely to happen to the curve in the diagram if the amorphous polymer is replaced by a thermosetting type?