The Law of Conservation of Mass says that mass can neither be
nor
A .Gained, lost
B. Created, destroyed
C. Started, ended
D. Opened, closed

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. give this information, how many electrons does it have? how many proteins and neutrons does this atom have

Ican determine the molar mass of an element by looking on the under the atomic mass for the element. for example the molar mass of phosphorus is 30.974 grams/mole. avogadro’s number tells me the amount of representative particles in 1 mole of any substance. this means 12.011 gram sample of carbon and a 32.0 gram sample of sulfur have the same number of atoms.

Δu of , in kj/kg, as it isto k, (a)as a of , (b) at , (c) at .