To determine the correct symbol of the nuclide given that it has 49 protons and 62 neutrons, follow these steps:
1. Identify the Atomic Number (Z):
- The atomic number (Z) corresponds to the number of protons in the nucleus of the atom.
- Given: The nuclide has 49 protons.
- Therefore, the atomic number [tex]\( Z = 49 \)[/tex].
2. Calculate the Atomic Mass Number (A):
- The atomic mass number (A) is the sum of the protons and neutrons in the nucleus.
- Given: The nuclide has 49 protons and 62 neutrons.
- Thus, the atomic mass number [tex]\( A = 49 + 62 = 111 \)[/tex].
3. Construct the Symbol of the Nuclide:
- The symbol of a nuclide is generally written as [tex]\({}_{Z}^{A} \text{Element}\)[/tex], where [tex]\( Z \)[/tex] is the atomic number and [tex]\( A \)[/tex] is the atomic mass number.
- For the given nuclide:
- Atomic number [tex]\( Z = 49 \)[/tex]
- Atomic mass number [tex]\( A = 111 \)[/tex]
- Therefore, the symbol is [tex]\({}_{49}^{111} \ln\)[/tex].
4. Evaluate the Given Options:
- Option (1): [tex]\({}_{62}^{49} \ln\)[/tex] — This option incorrectly places the atomic number and the atomic mass number.
- Option (2): [tex]\(62 \ln\)[/tex] — This option fails to specify both the atomic number and atomic mass number correctly.
- Option (3): [tex]\({}_{111}^{49} \ln\)[/tex] — This option incorrectly places the atomic number and the atomic mass number.
- Option (4): [tex]\({}_{49}^{111} \ln\)[/tex] — This option correctly identifies the atomic number [tex]\( Z = 49 \)[/tex] and the atomic mass number [tex]\( A = 111 \)[/tex].
Thus, the correct symbol of the nuclide is [tex]\({}_{49}^{111} \ln\)[/tex]. Therefore, the correct option is:
[tex]\[
\boxed{4}
\][/tex]
