CHEMISTRY REGENTS HELP
Based on your Chemistry Regents study guide, here are Unit-by-Unit Regents Flashcards covering the most-tested concepts. These are designed for quick review before the exam.
Unit 1: Introduction to Chemistry
Q: What is chemistry?
A: The study of matter and how it changes.
Q: What is density?
A: Mass divided by volume.
Q: What units are commonly used for density?
A: g/mL or g/L.
Q: What is dimensional analysis?
A: A method of converting units using conversion factors.
Q: Which zeros are significant?
A: Sandwiched zeros and ending zeros with a decimal point.
Q: What does a negative exponent in scientific notation mean?
A: The number is smaller than 1.
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Unit 2: Physical Behavior of Matter
Q: What is a physical property?
A: A property observed without changing composition.
Q: What is a chemical property?
A: A property describing a substance's ability to undergo chemical change.
Q: Which phase changes absorb energy?
A: Melting, evaporation, sublimation.
Q: Which phase changes release energy?
A: Freezing, condensation, deposition.
Q: During a phase change, what stays constant?
A: Temperature and average kinetic energy.
Q: What equation is used for calorimetry?
A: Q = mCΔT.
Q: What equation is used for heat of fusion?
A: Q = mHf.
Q: What equation is used for heat of vaporization?
A: Q = mHv.
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Unit 3: Gases
Q: What does Kinetic Molecular Theory state?
A: Gas particles move constantly and randomly.
Q: Boyle's Law relationship?
A: Pressure and volume are inversely related.
Q: Charles's Law relationship?
A: Volume and temperature are directly related.
Q: Gay-Lussac's Law relationship?
A: Pressure and temperature are directly related.
Q: What temperature unit must be used in gas laws?
A: Kelvin.
Q: At STP, one mole of gas occupies what volume?
A: 22.4 L.
Q: What happens to vapor pressure when intermolecular forces are weak?
A: Vapor pressure increases.
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Unit 4: The Atom
Q: Who proposed the Gold Foil Experiment?
A: Ernest Rutherford.
Q: What did Rutherford discover?
A: Atoms are mostly empty space with a dense positive nucleus.
Q: Charge of a proton?
A: +1.
Q: Charge of a neutron?
A: 0.
Q: Charge of an electron?
A: -1.
Q: Atomic number equals what?
A: Number of protons.
Q: Mass number equals what?
A: Protons + neutrons.
Q: What is an isotope?
A: Same element, different number of neutrons.
Q: What is a cation?
A: Positive ion formed by losing electrons.
Q: What is an anion?
A: Negative ion formed by gaining electrons.
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Unit 5: Periodic Table
Q: Periods run which direction?
A: Horizontal.
Q: Groups run which direction?
A: Vertical.
Q: What trend increases left and down?
A: Atomic radius and metallic character.
Q: What trend increases right and up?
A: Electronegativity and ionization energy.
Q: Most electronegative element?
A: Fluorine.
Q: Group 1 elements?
A: Alkali metals.
Q: Group 17 elements?
A: Halogens.
Q: Group 18 elements?
A: Noble gases.
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Unit 6: Chemical Bonding
Q: Ionic bonds occur between what types of elements?
A: Metals and nonmetals.
Q: Covalent bonds occur between what types of elements?
A: Two nonmetals.
Q: Metallic bonding involves what?
A: A sea of mobile electrons.
Q: What is a polar covalent bond?
A: Unequal sharing of electrons.
Q: What is a nonpolar covalent bond?
A: Equal sharing of electrons.
Q: Strongest IMF?
A: Hydrogen bonding.
Q: Hydrogen bonding occurs with H bonded to what three elements?
A: F, O, or N.
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Unit 7: Stoichiometry / Math of Chemistry
Q: How many particles are in 1 mole?
A: 6.02 × 10²³.
Q: Volume of 1 mole of gas at STP?
A: 22.4 L.
Q: What law states matter cannot be created or destroyed?
A: Law of Conservation of Matter.
Q: Five reaction types?
A: Synthesis, decomposition, single replacement, double replacement, combustion.
Q: What is a hydrocarbon?
A: Compound containing only carbon and hydrogen.
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Unit 8: Solutions
Q: What is the solute?
A: Substance being dissolved.
Q: What is the solvent?
A: Substance doing the dissolving.
Q: What is a saturated solution?
A: Cannot dissolve more solute.
Q: What is an unsaturated solution?
A: Can dissolve more solute.
Q: What is a supersaturated solution?
A: Contains more dissolved solute than normally possible.
Q: What does Table G show?
A: Solubility curves.
Q: What does Table F show?
A: Solubility rules.
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Unit 9: Kinetics & Equilibrium
Q: What is activation energy?
A: Minimum energy required for a reaction to occur.
Q: What does a catalyst do?
A: Lowers activation energy.
Q: What is an exothermic reaction?
A: Releases energy.
Q: What is an endothermic reaction?
A: Absorbs energy.
Q: At equilibrium, what is true about reaction rates?
A: Forward rate = reverse rate.
Q: What principle explains shifts in equilibrium?
A: Le Chatelier's Principle.
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Unit 10: Acids & Bases
Q: pH less than 7 means?
A: Acidic.
Q: pH greater than 7 means?
A: Basic.
Q: pH of a neutral solution?
A: 7.
Q: Acids are proton ______?
A: Donors.
Q: Bases are proton ______?
A: Acceptors.
Q: Products of neutralization?
A: Salt and water.
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Unit 11: Redox
Q: LEO says what?
A: Loss of Electrons = Oxidation.
Q: GER says what?
A: Gain of Electrons = Reduction.
Q: Where does oxidation occur?
A: Anode.
Q: Where does reduction occur?
A: Cathode.
Q: What mnemonic helps remember this?
A: AN OX, RED CAT.
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Unit 12: Organic Chemistry
Q: What is an alkane?
A: Hydrocarbon with only single bonds.
Q: What is an alkene?
A: Hydrocarbon with a double bond.
Q: What is an alkyne?
A: Hydrocarbon with a triple bond.
Q: What are isomers?
A: Same molecular formula, different structures.
Q: What must carbon always form?
A: Four bonds.
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Unit 13: Nuclear Chemistry
Q: What is a radioisotope?
A: An unstable isotope that undergoes decay.
Q: What is alpha decay?
A: Release of a helium nucleus.
Q: What is beta decay?
A: Release of an electron.
Q: What is gamma decay?
A: Release of energy only.
Q: What is half-life?
A: Time needed for half of a radioactive sample to decay.
Q: Difference between fission and fusion?
A: Fission splits nuclei; fusion combines nuclei.
These are the highest-yield flashcards for the Chemistry Regents and cover the major concepts from every unit in your study guide.