Question

It is possible to define metallic character as we do in this book and base it on the reactivity of the element and the ease with which it loses electrons. Alternatively, one could measure how well electricity is conducted by each of the elements to determine how "metallic" the elements are. On the basis of conductivity, there is not much of a trend in the periodic table: Silver is the most conductive metal, and manganese the least. Look up the first ionization energies of silver and manganese; which of these two elements would you call more metallic based on the way we define it in this book?

Short answer

Based on the first ionization energies, silver (Ag) has an ionization energy of 7.576 eV (or 731.0 kJ/mol), while manganese (Mn) has an ionization energy of 7.434 eV (or 717.4 kJ/mol). The lower the ionization energy, the more metallic the element is since it loses electrons more easily. Since manganese's ionization energy is lower than that of silver, manganese is deemed to be more metallic.

Step-by-step solution

Look up the first ionization energies of silver and manganese

Use a periodic table or other reference source to find the first ionization energies of silver and manganese. Ionization energy is usually expressed in electron volts (eV) or kilojoules per mole (kJ/mol).

Write down the ionization energies of silver and manganese

The first ionization energies for silver (Ag) and manganese (Mn) are as follows: Ag: 7.576 eV (or 731.0 kJ/mol) Mn: 7.434 eV (or 717.4 kJ/mol)

Compare the ionization energies

Compare the ionization energies of silver and manganese. Remember that the element with the lower ionization energy is considered more metallic, as it loses electrons more easily. Ag: 7.576 eV (or 731.0 kJ/mol) Mn: 7.434 eV (or 717.4 kJ/mol) Since 7.434 eV (Mn) is less than 7.576 eV (Ag), manganese has a lower ionization energy than silver.

Determine which element is more metallic

Based on the comparison of the ionization energies, manganese has a lower ionization energy than silver, which means manganese is more likely to lose electrons more easily. Thus, based on the metallic character definition given in the problem, we can conclude that manganese is more metallic than silver.

Key concepts

Ionization Energy

Ionization energy is a fundamental concept in chemistry, referring to the energy required to remove an electron from a gaseous atom or ion. It is measured in units like electron volts (eV) or kilojoules per mole (kJ/mol). Understanding ionization energy is crucial because it provides insight into the reactivity and chemical behavior of elements.

When comparing elements, those with lower ionization energy require less energy to lose an electron. This often indicates a stronger metallic character, as metals typically lose electrons easily during chemical reactions.

For instance, in the exercise presented, manganese has a first ionization energy of 7.434 eV, which is lower than silver's 7.576 eV. This difference suggests that manganese can lose an electron more readily than silver, aligning with its classification as more metallic according to our parameters.

Key points to remember about ionization energy include:

• A lower ionization energy implies a higher tendency for an element to undergo reactions by losing electrons.
• This property is crucial for determining how elements interact chemically, especially in metals.
• Reactivity in metals is often linked to how easily they can lose electrons, reflected in their ionization energy.

Reactivity of Elements

The reactivity of elements describes how easily they engage in chemical reactions. It directly correlates with their ability to lose or gain electrons. In the context of metallic character, reactivity is often assessed by how easily the element can lose electrons.

Metals, in particular, are generally reactive because they tend to lose electrons and form positive ions. Elements with lower ionization energies will typically exhibit higher reactivity among metals.

For example, manganese, which has a lower ionization energy compared to silver, demonstrates a stronger tendency to react and lose electrons. This increased reactivity underscores its more pronounced metallic character as defined by its ionization properties.

Consider these aspects when examining reactivity:

• An element’s position on the periodic table can hint at its reactivity, with metals on the left often being more reactive.
• Chemical reactivity is influenced by an element’s electron configuration and the stability achieved by losing or gaining electrons.
• Understanding reactivity is critical for predicting how different elements might behave in a chemical reaction.

Periodic Table Trends

The periodic table is a powerful tool for predicting and understanding element properties, including metallic character, ionization energy, and reactivity. Trends observed in the table help in making these predictions more consistently.

One clear trend is that ionization energy tends to increase across a period from left to right, as elements become less metallic and, typically, more nonmetallic. Conversely, ionization energy decreases down a group as outer electrons are further from the nucleus, making them easier to remove.

Manganese and silver, for instance, belong to different periodic groups, and their behaviors reflect typical trends. Manganese, positioned with other transition metals, reflects a lower ionization energy compared to some noble metals like silver, leading to its higher metallic character in certain conditions.

Important periodic trends to remember include:

• As you move across a period (left to right), elements generally show increased ionization energies and decreased metallic character.
• As you move down a group (top to bottom), ionization energy decreases, and elements often exhibit more metallic characteristics.
• Understanding these trends aids in predicting properties like reactivity and bonding behavior across the periodic table.