An element X exists as three naturally occurring isotopes. If all isotopes have the same atomic number, what would be the difference in the three isotopes?

Which statement describes how phase changes can be diagrammed as a substance is heated? the phase is on the y-axis and the temperature is on the x-axis. the temperature is on the y-axis and the phase is on the x-axis. the time is on the y-axis and the temperature is on the x-axis. the temperature is on the y-axis and the time is on the x-axis.

Calculate the number of molecules present in 0.750 mol of mgo.

What is the standard unit of measure for acceleration?