Atomic structure and the Periodic Table：練習題

An atom of an element has the electronic configuration 2, 8, 7.
In which Group and Period of the Periodic Table is this element located?

A neutral atom has 19 electrons. What is its electronic configuration and what group and period does it belong to?

Four particles, \(\text{J}\), \(\text{K}^+\), \(\text{L}^{2-}\), and \(\text{M}^{3-}\), have the following numbers of electrons and neutrons:

\(\bullet\text{ Particle J: } 18\text{ electrons, } 22\text{ neutrons}\)
\(\bullet\text{ Particle K}^+: 18\text{ electrons, } 21\text{ neutrons}\)
\(\bullet\text{ Particle L}^{2-}: 18\text{ electrons, } 18\text{ neutrons}\)
\(\bullet\text{ Particle M}^{3-}: 10\text{ electrons, } 8\text{ neutrons}\)

Which pair of particles has the same nucleon number?

Which statement correctly describes the trend in Group VII elements (the halogens) as the atomic number increases?

An atom of element \(\text{M}\) has a nucleon number of \(11\) and contains \(6\) neutrons. Which row correctly gives the electronic configuration of an atom of \(\text{M}\) and identifies its position in the Periodic Table?

State the relative charge and relative mass of a neutron.

Explain why isotopes of the same element, such as \( ^{12}_{6}C \) and \( ^{14}_{6}C \), exhibit identical chemical properties.

An element is located in Period 3 of the Periodic Table and forms an ion with a charge of \( 2- \). Determine the electronic configuration of the neutral atom and identify its Group number.

Element X has a proton number of 17 and a mass number of 35.

a) State the number of protons, neutrons, and electrons in a neutral atom of X.

b) Write the electronic configuration of atom X.

c) Explain why element X is placed in Group VII of the Periodic Table.

Table 1 provides information about four different particles, \(\text{A}\), \(\text{B}\), \(\text{C}\), and \(\text{D}\).

Table 1

(a) (i) Identify which particle from Table 1 is a cation. Explain your choice in terms of subatomic particles.
(ii) Give the formula, including the charge, of particle \(\text{A}\) using its chemical symbol from the Periodic Table.

(b) State the term used to describe the relationship between particle \(\text{C}\) and particle \(\text{D}\) with respect to their atomic nuclei. Explain why neutral atoms of \(\text{C}\) and \(\text{D}\) share identical chemical properties.

(c) Particle \(\text{B}\) is a neutral atom.
(i) State the Group and Period of the Periodic Table to which element \(\text{B}\) belongs.
(ii) Explain how the electronic configuration of particle \(\text{B}\) determines its Group and Period.