Straighterline CHEM101 General Chemistry I ALL EXAMS (2025/2026) QUESTIONS WITH CORRECT DETAILED ANSWERS || 100% GUARANTEED PASS!! <RECENT UPDATE>

Straighterline CHEM101 General Chemistry I ALL EXAMS (2025/2026) QUESTIONS WITH CORRECT DETAILED ANSWERS || 100% GUARANTEED PASS!! &lt;RECENT UPDATE&gt; Electron affinity - ANSWER the energy change that occurs when an electron is acquired by a neutral atom Electronegativity - ANSWER A measure of the ability of an atom in a chemical compound to attract electrons Chemical bonding - ANSWER The joining of atoms to form new substances Lewis structure - ANSWER A model that uses electron-dot structures to show how electrons are arranged in molecules. Pairs of dots or lines represent bonding pairs. Molecule - ANSWER A group of atoms bonded together Molecular shape - ANSWER determines how biological molecules recognize and respond to one another VSPER - ANSWER Valence Shell Electron Pair Repulsion Electron pair - ANSWER two electrons occupying the same orbital in an atom or molecule Electron domain - ANSWER a lone pair or a bond, regardless of whether the bond is single, double, or triple Bonding e- domain - ANSWER These are e- directly involved in covalent bonds between 2 atoms Non-bonding e- domain - ANSWER these are iome e- pairs SI units - ANSWER a system of physical units ( SI Units ) based on the meter, kilogram, second, ampere, kelvin, candela, and mole, together with a set of prefixes to indicate multiplication or division by a power of ten. Unit conversion - ANSWER The process of changing one unit of measure to another. Temperature scales - ANSWER Fahrenheit, Celsius, Kelvin Scientific notation - ANSWER a method of expressing a quantity as a number multiplied by 10 to the appropriate power Positive exponent - ANSWER move decimal to the right Negative exponent - ANSWER take the reciprocal and change the exponent to positive Determine error - ANSWER comes from lack of experience or ability Rules for recording significant figures - ANSWER Non-zero digits are always significant. All zeros between other significant digits are significant. The number of significant figures is determined by starting with the leftmost non zero digit. The leftmost non-zero digit is sometimes called the most significant digit or the most significant figure. For example, in the number 0.004205, the '4' is the most significant figure. The left-hand '0's are not significant. The zero between the '2' and the '5' is significant. Rules for rounding significant figures - ANSWER 1. If the digit to the right of the last sf is less than 5, do not change the last sf (2.532-&gt;2.53) 2. If the digit to the right of the last sf is greater than 5, round up the last sf (2.536 &gt;2.54) (3+4-rule of 5-even) 3. If the digit to the right of the last sf are a 5 followed by a nonzero digit, round up the last sf (2.531-&gt;2.54) 4. If the digits to the right of the last sf are a 5 followed by a 0 or no other number, look at the last sf. If it is odd, round it up; if it is even, do not round up (2.5350 &gt;2.54 or 2.5250-&gt;2.52) Significant figures and math operation - ANSWER rules for multiple operation and division, the results should have the same kind of sig figures as the number with the fewest amounts of sig Rules for addition and subtraction - ANSWER the answer has the same number of decimal places as the original number with the fewest decimal places Photoelectric effect - ANSWER - demonstrates the particle nature of light - an electron can be ejected from the surface of a metal by shining light of a certain frequency on it - only occurs when the incoming light (*photon*) overcomes the *work function* (minimum energy to eject he electron) Intramolecular bonding - ANSWER - ionic bonding - covalent bonding Polar covalent bond - ANSWER - occurs when 2 atoms of electronegativity form a covalent bond - the electrons are not shared equally - contains a dipole (µ) Dipole moment - ANSWER - points to the more electron rich (δ-) region - has magnitude and direction (vector) Pure covalent bonds - ANSWER - occurs when 2 atoms are identical - electronegativity difference is zero so electrons are shared equally Symmetric covalently-bonded molecules - ANSWER - no net dipole moment - individual dipoles cancel out in 3D space Intermolecular bonding - ANSWER - the weak interactions between molecules - London dispersion forces (induced-dipole-induced-dipole) - dipole-dipole forces - hydrogen bonding Increased intermolecular forces - ANSWER increased boiling point and melting point London dispersion forces - ANSWER - arise from the formation of an instantaneous dipole in the electron cloud of a given molecule - cause induced dipoles in nearby molecules - possessed by all atoms and molecules Large London dispersion forces - ANSWER - in single atoms with a large number of electrons (and low electronegativity) - in large molecules with multiple electron clouds - in atoms or molecules where the electron cloud can easily polarize (shift) Dipole-dipole forces - ANSWER - arise from the formation of permanent dipoles between atoms/molecules Hydrogen bonding - ANSWER - arise from the sharing of lone pair electrons between a highly electronegative atom (F, O, N) with a positively polarized hydrogen atom Radioactive - ANSWER - nuclei which are unstable Radioactive decay - ANSWER - transformations that allow radioactive nuclei to become more stable over time - the number of protons and/or neutrons change - first order process