Question

1. what is the symbol for the element with atomic #82?
2. what is the name of the element with the symbol h?
3. what subatomic particles are in an uncharged isotope with atomic number 20 and 45 nucleons?
4. what subatomic particles are in ag⁺ if its mass number is 108?
5. what is the isotope name for a nucleus with 36 protons and 56 neutrons?
6. what is the atomic number for bismuth?
7. what is the atomic number for se?

Explanation:

Step1: Recall periodic - table lookup

The element with atomic number 82 is lead, symbol Pb.

Step2: Recall element symbol - name correspondence

The symbol H corresponds to hydrogen.

Step3: Use atomic - number and nucleon - number relationships

For an uncharged isotope with atomic number (Z) 20 and nucleon number (A) 45, number of protons = Z = 20, number of neutrons = A - Z=45 - 20 = 25, and number of electrons = number of protons in an uncharged atom = 20.

Step4: Identify subatomic particles in an ion

Silver (Ag) has atomic number 47. For Ag⁺ with mass number 108, number of protons = 47, number of neutrons = 108 - 47 = 61, and number of electrons = 47 - 1 = 46 (due to + 1 charge).

Step5: Name an isotope

An element with 36 protons is krypton (Kr). Mass number = 36+56 = 92, so the isotope is krypton - 92.

Step6: Look up atomic number of bismuth

Bismuth has atomic number 83.

Step7: Look up atomic number of Se

Selenium (Se) has atomic number 34.

Answer:

1. Pb
2. Hydrogen
3. # p⁺: 20; # n⁰: 25; # e⁻: 20
4. # p⁺: 47; # n⁰: 61; # e⁻: 46
5. Krypton - 92
6. 83
7. 34