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.