Astable nuclide exists when the overcomes the between positively charged protons.
a. electrostatic attraction, strong force
b. electrostatic repulsion, strong force
c. strong force, electrostatic attraction
d. strong force, electrostatic repulsion

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.