Question

1. how many electrons can an orbital contain?

a. 1
b. 2
c. 3
d. 4

1. what is the electron configuration for tin (sn)?

a. kr5s²3d¹⁰3f⁴5p⁴
b. kr5s²3d¹⁰4d¹⁴5p⁴
c. kr5s²3d¹⁰4f⁴5p²
d. kr5s²4d¹⁰5p²

1. what is an electron dot structure?

a. an element symbol surrounded by dots representing its valence electrons.
b. an element symbol surrounded by its innermost electrons.
c. an element symbol with a positive charge.
d. a filled noble gas in brackets plus the remaining electron configuration expressed by filled orbitals.

1. why does the 4s orbital begin to fill before the 3d orbital?

a. the 4s orbital is lower than the 3d orbital in the aufbau diagram.
b. s orbitals always fill before d orbitals.
c. the 4s orbital is to the left of the 3d orbital in the diagram.
d. the 4s orbital has higher energy than the 3d orbital.

1. which of the following statements expresses hunds rule?

a. electrons in orbitals must possess opposite spins.
b. single electrons with the same spin must occupy each equal - energy orbital before additional electrons with opposite spins can occupy the same orbitals.
c. electrons with the same spin fill all orbitals.
d. p orbitals may contain up to six electrons.

1. the smallest particle of an element that retains all the properties of that element; is electrically neutral, spherically shaped, and composed of electrons, protons, and neutrons.

a. atom
b. proton
c. electron
d. neutron

1. a neutral, subatomic particle in an atoms nucleus that has a mass nearly equal to that of a proton.

a. neutron
b. electron
c. proton
d. atom

1. a reaction that involves a change in the nucleus of an atom

a. nuclear reaction
b. nuclear equation
c. alpha radiation
d. beta radiation

Explanation:

• Question 26: According to the Pauli exclusion principle, an orbital can hold a maximum of 2 electrons with opposite spins.
• Question 27: Tin (Sn) has an atomic number of 50. Using the Aufbau principle, its electron configuration is \([Kr]5s^{2}4d^{10}5p^{2}\).
• Question 28: An electron - dot structure (Lewis structure) is an element symbol surrounded by dots representing its valence electrons.
• Question 29: In the Aufbau diagram, the 4s orbital has a lower energy than the 3d orbital, so it fills first.
• Question 30: Hund's rule states that single electrons with the same spin must occupy each equal - energy orbital before additional electrons with opposite spins can occupy the same orbitals.
• Question 31: An atom is the smallest particle of an element that retains all the properties of that element, is electrically neutral, spherically shaped, and composed of electrons, protons, and neutrons.
• Question 32: A neutron is a neutral, subatomic particle in an atom's nucleus that has a mass nearly equal to that of a proton.
• Question 33: A nuclear reaction is a reaction that involves a change in the nucleus of an atom.

Answer:

1. B. 2
2. D. \([Kr]5s^{2}4d^{10}5p^{2}\)
3. A. An element symbol surrounded by dots representing its valence electrons.
4. A. The 4s orbital is lower than the 3d orbital in the Aufbau diagram.
5. B. Single electrons with the same spin must occupy each equal - energy orbital before additional electrons with opposite spins can occupy the same orbitals.
6. A. Atom
7. A. Neutron
8. A. Nuclear reaction