D has a total of four significant figures.
B. is ur answer I bieleve
Proton number = the atomic number (which is the smaller number
neutron number = the mass number (the bigger number) - the atomic number
number of electrons = the atomic number - the charge (it depends on the element but group 1 is +1 group 2 is +2 group 3 is +3 group five is -3 group six is -2 group seven is -1
i would solve the whole thing but its unclear hope this helps tho
I would believe it to be 55g. A -> B YIELDS AB. So, 10g + 45g = 55g.
