Calculate the total number of hydrogen atom and molecule present in 1.7gram of ammonia

What is the percent by mass of oxygen in fe2o3

What does the field of thermodynamics relate to a-changes in nuclear reactions b- changes in energy in systems c changes in molecular structure d changes in atomic properties

Consider the heating curve of h2o and line segments a, b, and c. several changes are taking place at a, b, and c. all but one would be an appropriate description as e move through segments a, b and then c.