Which Element Has A Mass Number Of 39 And 20 Neutrons?
Which Element Has A Mass Number Of 39 And 20 Neutrons? #19 – Potassium – K. What element has a mass number of 39? Atomic Mass Name chemical element number 85.4678 Rubidium 37 87.62 Strontium 38 88.9059Yttrium 39 91.224 Zirconium 40 What element has a mass of 39 and 20 neutrons? The atomic mass of