Question

If the neutron of an element A is 20 with proton 19, the atomic mass is 39. If the neutron of B is decreased by 4 as compare with element A & the proton is still 19, what is the number of electrons, neutrons, atomic# & mass of B?

Answer 1

If Element A has 19 protons and 20 neutrons, its atomic mass is 39. This suggests that the element is potassium (K), as potassium's atomic number is 19 and its atomic mass is approximately 39.

Now, let's consider Element B. It has the same number of protons as Element A (19), but the neutron count is decreased by 4.

Neutrons in Element B = Neutrons in Element A - 4 Neutrons in Element B = 20 - 4 Neutrons in Element B = 16

To determine the number of electrons in an atom, we need to know the atomic number. Since Element B has 19 protons, the atomic number is also 19.

Therefore, for Element B:

• Protons: 19
• Neutrons: 16
• Electrons: 19
• Atomic number: 19
• Atomic mass: Protons + Neutrons = 19 + 16 = 35