Atoms are made of 3 types of subatomic particles ; protons, neutrons and electrons
protons and neutrons are located inside the nucleus and electrons are found in energy shells around the nucleus. Protons are positively charged, electrons are negatively charged and neutrons are neutral. elements in their ground state are neutral with equal amounts of protons and electrons.
Atomic number is the number of protons. atomic number is characteristic for the element.
atomic number of Be is 4 therefore Be has 4 protons
Beryllium has an atomic number of four so has four protons in its nucleus. The atomic number shows how many protons are in the nucleus so once this number is known then the answer can be ascertained and recorded as such.
Balanced equation: Mg+2HCl=MgCl2 + H2 Showing that if Mg is not a limiting factor then 2 moles of HCl on complete reaction liberate 1 mole of Hydrogen therefore: 1 mole of HCl=35.5g, 40g=x X= 40/35.5= 1.127mole 2 moles of HCl = 1 moles of Hydrogen 1.127=X X=1.127/2 = 0.56 the theoretical yield of hydrogen
