Question

what is the missing particle?

$\

$$\begin{array}{r} 147 \\\\ 62 \\end{array}$$

sm \to \

$$\begin{array}{r} 4 \\\\ 2 \\end{array}$$

he + \square{?}$

$\

$$\begin{array}{r} 143 \\\\ 62 \\end{array}$$

nd$

$\

$$\begin{array}{r} 143 \\\\ 60 \\end{array}$$

sm$

$\

$$\begin{array}{r} 143 \\\\ 60 \\end{array}$$

nd$

Explanation:

Step1: Determine the mass number of the missing particle

The mass number of \(^{147}_{62}\text{Sm}\) is \(147\), and the mass number of \(^{4}_{2}\text{He}\) is \(4\).
Using the conservation of mass number: \(147 = 4+\text{mass number of missing particle}\).
So, the mass number of the missing particle is \(147 - 4=143\).

Step2: Determine the atomic number of the missing particle

The atomic number of \(^{147}_{62}\text{Sm}\) is \(62\), and the atomic number of \(^{4}_{2}\text{He}\) is \(2\).
Using the conservation of atomic number: \(62=2 + \text{atomic number of missing particle}\).
So, the atomic number of the missing particle is \(62 - 2 = 60\).

Step3: Identify the element

Looking at the periodic table, the element with atomic number \(60\) is Neodymium (\(\text{Nd}\)).

Answer:

\(^{143}_{60}\text{Nd}\)