Cyclohexane (δh° = 936 kcal/mol ) and methylcyclopentane (δh° = 941 kcal/mol) have the same molecular formula but different strain. why? sort true and false statements.

The difference of the structures of the two isomers are shown in the picture. Generally, cyclic alkanes are much easier to break than straight-chained alkanes. When the molecules are cyclic, they are close to each other, thus lesser bond angles. Because they are closer, repulsion forces could be greater than attractive forces. That is why cyclohexane needs lesser energy of 936 kcal/mol compared to 941 kcal/mol because there is an additional straight-chained methyl substituent to break in methylcyclopentane.

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. 

C) electrons encircling a nucleus with neutrons and protons