At elevated temperatures, methylisonitrile (CH₃NC) converts to acetonitrile (CH₃CN):

At the start of the experiment, there are 0.200 mol of reactant (CH₃NC) and 0 mol of product (CH₃CN) in the reaction vessel. After 25 min of reaction, 0.108 mol of reactant (CH₃NC) remain. The average rate of decomposition of methyl isonitrile, CH₃NC, in this 25 min period is mol/min.

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant. 

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Hello thereone of the following properties was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version. which property fits this description? answer: atomic mass  was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.