Question

If an element forms an ionic hydride, is it more likely to form an acidic or basic oxide?

Short answer

Elements forming ionic hydrides usually form basic oxides.

Step-by-step solution

Understanding Ionic Hydrides

Ionic hydrides are formed when an element, usually a metal, bonds with hydrogen by donating electrons to hydrogen. These elements are often from Groups 1 and 2 on the periodic table, like lithium (Li), sodium (Na), and calcium (Ca), which are known for their metallic properties.

Properties of Elements Forming Ionic Hydrides

Elements that form ionic hydrides tend to be highly electropositive metals. These elements have low electronegativity, which means they are more likely to lose electrons and form positive ions. Typically, such metals also form basic oxides when they react with oxygen.

Acidic vs Basic Oxides

An oxide is considered basic if it reacts with water to form a base (an alkali) or with an acid to form a water and salt. Conversely, an oxide is acidic if it reacts with a base to form water and a salt. Generally, metals of lower electronegativity form oxides that are basic, while non-metals tend to form acidic oxides.

Analysis and Conclusion

Since elements that form ionic hydrides are typically metals and tend to have basic properties, their oxides are more likely to be basic. This is because highly electropositive metals form metal cations that combine with oxygen to produce basic oxides.

Key concepts

Acidic Oxides

Acidic oxides are oxides that typically arise from non-metals. These oxides react with bases to create water and salts, making them acidic in nature. An example of an acidic oxide is carbon dioxide (\( CO_2 \)) which reacts with bases like sodium hydroxide (\( NaOH \)) to form sodium carbonate (\( Na_2CO_3 \)).
Non-metallic elements tend to have higher electronegativity, allowing them to attract electrons more strongly, resulting in acidic oxide formation. These oxides do not possess the properties that are commonly associated with metallic substances. Acidic oxides have the following characteristics:

• Formed from non-metals
• React with bases
• Have covalent bonds

Acidic oxides are crucial in various chemical reactions and play a significant role in environmental chemistry, influencing phenomena such as acid rain.

Basic Oxides

Basic oxides are primarily formed from metallic elements from the left side of the periodic table. These oxides react with acids to yield salts and water, making them basic. Metallic elements like sodium (\( Na \)) and potassium (\( K \)) often form basic oxides when they react with oxygen. For instance, sodium oxide (\( Na_2O \)) reacts with water to produce sodium hydroxide (\( NaOH \)).
The characteristics of basic oxides include:

• Formation by metals, especially alkali and alkaline earth metals
• Reaction with acids
• Cationic nature resulting in ionic bonds

These oxides play a vital role in various industrial processes, such as the production of soap and glass, due to their ability to neutralize acids.

Metallic Properties

Metallic properties are exhibited by elements that tend to easily lose electrons and form positive ions or cations. These properties are most strongly seen in the elements of Groups 1 and 2, such as lithium, sodium, and calcium. Metals have a shiny appearance, are good conductors of heat and electricity, and are malleable and ductile.
In terms of chemical behavior, metals:

• Have low electronegativity
• Form cations by losing electrons
• Readily form basic oxides

Understanding metallic properties helps us predict how these elements will behave in chemical reactions, including their ability to form ionic hydrides and basic oxides.

Groups 1 and 2 Elements

Groups 1 and 2 elements, also known as alkali and alkaline earth metals, occupy the far left of the periodic table. They are characterized by their single or double valence electrons, respectively, which they tend to lose easily.

Alkali metals include lithium (\( Li \)), sodium (\( Na \)), and potassium (\( K \)).

Alkaline earth metals encompass elements like magnesium (\( Mg \)) and calcium (\( Ca \)).

Because of their readiness to donate electrons, these elements exhibit strong metallic properties and form ionic and basic compounds, such as ionic hydrides and basic oxides. Groups 1 and 2 elements are crucial in many applications, from biological processes to industrial uses, due to their reactive nature and metallic characteristics.