How many atoms are in 11.5g of Hg

Measuring which physical property is most likely to produce the most precise results when trying to identify a substance

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.