IMG_1546.jpeg

## Honors Chemistry ## Chemical Bonding & Compounds Unit Study Guide ### Part A: Chemical Bonding & Compounds Vocabulary & Concepts 1. How does a cation form from a neutral atom? The neutral atom loses one or more electrons, forming a cation. 2. Show with a sketch how a calcium atom would b...

## Honors Chemistry ## Chemical Bonding & Compounds Unit Study Guide ### Part A: Chemical Bonding & Compounds Vocabulary & Concepts 1. How does a cation form from a neutral atom? The neutral atom loses one or more electrons, forming a cation. 2. Show with a sketch how a calcium atom would become a calcium cation: $Ca^{20} \rightarrow Ca^{2+} + e^- + e^-$ 3. How does an anion form from a neutral atom? The neutral atom gains one or more electrons, forming an anion. 4. Show with a sketch how an oxygen atom would become an oxide anion: $O^{8+} + e^- + e^- \rightarrow O^{2-}$ 5. Compare and contrast an atom's valence electrons to the other electrons in its structure: The valence electrons are higher in energy in the outermost occupied energy level, but otherwise have the same charge and mass as any other electron. 6. How many valence electrons will be in a neutral atom of each of the following elements: Na: 1 N: 5 Ar: 8 Mg: 2 S: 6 Cl: 7 7. Use the octet rule (rule of "filling the outer shell") to predict the charge if an atom of each of the following elements became a cation or anion: Na: $1^+$ N: $3^-$ Ar: 0 Mg: $2^+$ S: $2^-$ Cl: $1^-$ 8. How do ionic bonds hold atoms together? The oppositely charged cations and anions attract one another. 9. How can you tell the formula of an ionic compound apart from the formula of a molecular compound? Ionic compounds show a metal (or $NH_4^+$) ion at the beginning. 10. What is a polyatomic ion? Multiple atoms, bonded together, that function as an individual ion. 11. What does the chemical formula for an ionic compound, such as $Fe_2O_3$, mean about the composition of the substance? (i.e. describe the composition of the substance in detail) It tells the ratio of cations to anions in the larger crystal lattice structure. 12. What makes ionic compounds electrically neutral even though they are made of charged particles? The ratio of cations to anions will always be such that the positive charges exactly cancel the negatives. 13. If you find a compound that is a liquid at room temperature, has a melting point of -25°C, and does not conduct electricity, the compound is most likely made of molecules (ions/molecules) because its low melting point suggests that it is not a solid at room temp.