Title T1 BASCHEM LQ1 2025-2026 Notes.pdf ✅

2 To download reviewers and avail tutorials, visit: https://dlsu-syntax.vercel.app/ Society of Young Engineers Towards Achieving Excellence Tutorials | Reviewers BASCHEM Long Quiz 1 double, or triple bond which indicates how many pairs of electrons are shared between the two atoms. 1. Single Bond – atoms share one pair of e- 2. Double Bond – atoms share two pairs of e- 3. Triple Bond – atoms share three pairs of e- Example: 1. Water (H2O) 2. Oxygen gas (O2) 3. Ethyne (C2H2) Notes for examples: Each example shows the difference between each type of covalent bonding. Each line or bond signifies a pair of electrons. Observe that each of the atoms present in the examples follows the octet rule. Under this rule, atoms of elements other than hydrogen tend to form bonds until it is surrounded by eight valence electrons. Electronegativity Another property that is used in chemical bonding is electronegativity. It is the ability of an atom to attract itself to the electrons in a chemical bond. A higher electronegativity indicates a greater tendency to attract electrons than elements with low electronegativity. On the periodic table, electronegativity increases from left to right and decreases from top to down. This indicates that the most electronegative elements are on the top right of the periodic table. The electronegativity (EN) difference between two atoms that are chemically bonded indicates the type of bond that it exhibits. A covalent bond can be classified as polar or nonpolar. When there is an EN difference less than 0.3, there is a nonpolar covalent bond. When the EN difference is between 0.3 and 2.0, there is a polar covalent bond. When the EN difference is greater than 2.0, an ionic bond is formed. A polar covalent bond indicates that the electrons tend to spend more time in the vicinity of one atom than the other. Note: In the 13th Edition of the textbook, the EN difference is 0.4 instead of 0.3. Example: 1. Determine the type of bond formed by Hydrogen Fluoride. EN Difference = 4.0 – 2.1 = 1.9 Since the difference is between 0.4 and 2.0, Hydrogen Fluoride has a polar covalent bond. 2. Determine the type of bond formed by Potassium Chloride.