UNIT 3 CFA

A new material is being developed for use in airplane wings. The engineers are considering a metal, an ionic compound, and a covalent molecule. Based on your understanding of bonding and structure, which material would most likely provide the best combination of strength and malleability for this application? Justify your answer using evidence from the bonding and structure of each material.

• Ionic compound, because its strong ionic bonds make it both strong and flexible.

• Metal, because metallic bonding allows for delocalized electrons, resulting in both strength and malleability.

• covalent, because its covalent bonds make it the strongest and most malleable.

• Ionic compound, because its crystalline structure allows for easy deformation.

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A scientist is comparing the brittleness of three materials: a metal, an ionic compound, and a covalent molecule. Using your understanding of their bonding and structure, which material is most likely to be brittle and why?

• Metal, because metallic bonds are weak and break easily.

• Ionic compound, because the rigid crystalline structure and strong ionic bonds make it prone to shattering under stress.

• covalent molecule, because its flexible molecular chains make it brittle.

• Metal, because its delocalized electrons make it brittle.

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What type of bond is formed when electrons are transferred from one atom to another?

• Covalent bond

• Metallic bond

• Ionic bond

• Hydrogen bond

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Which of the following chemical formulas represents carbon dioxide?

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Which of the following best describes a double bond in a Lewis structure?

• Two atoms sharing one pair of electrons

• Two atoms sharing two pairs of electrons

• Two atoms sharing three pairs of electrons

• Two atoms sharing four pairs of electrons

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What is the correct chemical formula for magnesium chloride?

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Which of the following is an example of a covalent compound?

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Predict the type of bond that will form between potassium and bromine and justify your answer.

• Covalent, because both are nonmetals

• Ionic, because potassium is a metal and bromine is a nonmetal

• Metallic, because both are metals

• Covalent, because potassium is a noble gas

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Look at the picture and determine if it is accurate.

• The structure is correct because Nitrogen has 8 electrons

• The structure is correct because Nitrogen needs 8 Valence electrons to fulfill octet

• The structure is incorrect because Nitrogen needs 10 valence electrons and the image has 8 valence electrons

• The structure is incorrect because one nitrogen is missing its lone pairs.

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