Pierakstīties
WAEC - Chemistry (1997 - No. 2)
The mass number of an element is the sum of its
electrons, neutrons and protons
electrons and protons
protons and neutrons
orbital electrons
valence electrons
komentāri (0)
Piesakieties, lai komentētu
Reklāma
Ļaujiet javascript pareizi ielādēt šo lapu
