Observe: Turn on Show element symbol and Element notation. Three numbers surround the element symbol: the mass number (A), electrical charge (no number is displayed if the atom is neutral), and the atomic number (Z). Investigate: Watch how the numbers change as you add or remove particles.

A.
Which number is equal to the number of protons in the atom?

B.
How can you calculate the number of neutrons (N) in an atom?

C.
Which particle (proton, neutron, or electron) has a

Positive charge?

Negative charge?

No charge at all?

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.

alchemy hadn't scientific methods of study, appeal to mysticism and fantasy, the knowledge of chemistry and physics were modest at that time.

alchemy was - but as new rules were discovered it either changed into chemistry or it became "unscientific".