Question

an atom has a mass number of 66. if the number of neutrons in the nucleus is 1.2 times that of the number of protons, what is the chemical symbol of this element?

Explanation:

Step1: Set up equations

Let the number of protons be \(p\). The number of neutrons \(n = 1.2p\). The mass number \(A=p + n\). Given \(A = 66\).

Step2: Substitute and solve for \(p\)

Substitute \(n = 1.2p\) into \(A=p + n\). We get \(66=p+1.2p\). Combine like - terms: \(66 = 2.2p\). Then \(p=\frac{66}{2.2}=30\).

Step3: Identify the element

The number of protons \(p\) is the atomic number \(Z\). The element with \(Z = 30\) is zinc (\(Zn\)).

Answer:

\(Zn\)