Question

trudy writes an expression to calculate the mass defect of a carbon - 14 nucleus using the symbols in the table.
which expression should trudy write?
(6m_p + 8m_n) - m_{c - 14}
(8m_p + 6m_n) - m_{c - 14}
m_p + m_n - m_{c - 14}
6m_p + 8m_e - m_{c - 14}

Explanation:

Step1: Determine the number of protons and neutrons in carbon - 14

Carbon - 14 has an atomic number \(Z = 6\) (number of protons) and a mass number \(A=14\). The number of neutrons \(N=A - Z=14 - 6 = 8\).

Step2: Calculate the sum of the masses of protons and neutrons

The sum of the masses of protons and neutrons is \(6m_p+8m_n\) (since there are 6 protons and 8 neutrons).

Step3: Use the formula for mass defect

The formula for mass defect \(\Delta m\) is \(\Delta m=\text{(sum of masses of nucleons)}-\text{(mass of the nucleus)}\). So \(\Delta m=(6m_p + 8m_n)-m_{C - 14}\)

Answer:

\((6m_p + 8m_n)-m_{C - 14}\) (the first option)