A student made a sketch of a potential energy diagram to represent an endothermic reaction. A curve line graph is shown. The y axis of the graph has the title Potential Energy and kJ written in parenthesis. The x axis of the graph has the title Reaction Pathway. The curve begins at a higher level and ends at a slightly lower level. A broken horizontal line is shown from a point labelled X on the y axis to the point where the curve begins. Another broken horizontal line is shown from a point labeled Y on the y axis to the point where the curve ends. Explain, using complete sentences, why the diagram made by the student is correct or incorrect. Be sure to also explain what the values of X and Y represent.

Two nitro no2 groups are chemically bonded to a patch of surface. they can't move to another location on the surface, but they can rotate (see sketch at right). it turns out that the amount of rotational kinetic energy each no2 group can have is required to be a multiple of ε, where =ε×1.010−24 j. in other words, each no2 group could have ε of rotational kinetic energy, or 2ε, or 3ε, and so forth — but it cannot have just any old amount of rotational kinetic energy. suppose the total rotational kinetic energy in this system is initially known to be 32ε. then, some heat is removed from the system, and the total rotational kinetic energy falls to 18ε. calculate the change in entropy. round your answer to 3 significant digits, and be sure it has the correct unit symbol.

What is the percent by mass of oxygen in fe2o3

•what conclusions can you make about the relationship between the volume of a gas and its temperature? • what conclusions can you make about the relationship between the volume of a gas and its pressure? • what possible variables have you not accounted for? as you did the procedures, is it possible that the atmospheric pressure may have changed? if it did change over the course of your experiment, then how would your results have been affected?