Which model represents the ionic compound sodium oxide, $Na _2 O$ ?
A. Na
B. 2 Na
C. $Na : O _{\bullet \bullet}^{\bullet}: Na$
Answer (1)
Sodium oxide ( N a 2 O ) consists of N a + and O 2 − ions.
Option A is just a neutral sodium atom.
Option B is unclear and doesn't represent ionic bonding.
Option C, N a : O ∙∙ ∙ : N a , is the closest representation.
The correct answer is C.
Explanation
Understanding the Problem We want to determine which of the given options correctly represents the ionic compound sodium oxide, N a 2 O .
Determining the Charges In sodium oxide ( N a 2 O ), sodium (Na) is a group 1 element, so it loses one electron to form a +1 ion ( N a + ). Oxygen (O) is a group 16 element, so it gains two electrons to form a -2 ion ( O 2 − ). The compound consists of two sodium ions and one oxide ion.
Evaluating the Options Now, let's evaluate each option:
Option A: Na - This only shows a neutral sodium atom, not the ionic compound.
Option B: 2 Na ( ∵ 00 : − 2 - This option is unclear and doesn't properly represent the ionic bonding. It seems to indicate two neutral sodium atoms and a -2 charge, but it's not a correct representation of the compound.
Option C: N a : O ∙∙ ∙ : N a - This option shows two sodium atoms and one oxygen atom. The dots around the oxygen represent its valence electrons. In an ionic compound, electrons are transferred, so this representation is more accurate. It shows the sharing of electrons, which is not entirely correct for an ionic compound, but it's the closest representation among the options.
Conclusion Considering the options, option C, N a : O ∙∙ ∙ : N a , is the closest representation of the ionic compound sodium oxide, even though it uses a Lewis dot structure which is more appropriate for covalent compounds. It shows two sodium atoms and one oxygen atom, which is consistent with the formula N a 2 O .
Examples
Ionic compounds like sodium oxide ( N a 2 O ) are essential in various applications, such as in the production of ceramics and glasses. Understanding how these compounds are formed through ionic bonding helps in predicting their properties and applications. For instance, the strong electrostatic forces between N a + and O 2 − ions in N a 2 O contribute to its high melting point and stability. This knowledge is crucial in materials science for designing and synthesizing new materials with specific properties.
