Question

electrons: _
neutrons: _
protons: _
silicon
si
14
28.09

Explanation:

Step1: Recall atomic number and proton - electron relationship

The atomic number of an element is equal to the number of protons. For silicon (Si), the atomic number is 14, so the number of protons is 14. In a neutral atom, the number of electrons is equal to the number of protons. So the number of electrons is also 14.

Step2: Calculate the number of neutrons

The mass number (rounded to the nearest whole number) is approximately equal to the sum of protons and neutrons. The atomic mass of Si is 28.09. Rounding it to 28. The number of neutrons = mass number - number of protons. So the number of neutrons = 28 - 14=14.

Answer:

Electrons: 14
Neutrons: 14
Protons: 14