Chemistry Section 5

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• According to Gay-Lussac’s law, when gases react, they do so in simple whole-number ratios by volume.
• The normal boiling point is the temperature at which the vapor pressure of a liquid equals 1 atm.
• For a given mass of gas at constant temperature, its volume is inversely proportional to pressure.
• The SI unit of pressure is the pascal (Pa).
• According to Avogadro’s hypothesis, equal volumes of gases at the same temperature and pressure contain an equal number of molecules.
• Diffusion is faster in gases compared to liquids.
• The movement of water molecules across a selectively permeable membrane is osmosis.
• The molecular weight of glucose is 180 g/mol.
• Hemodialysis is an artificial method of filtration used in cases of kidney failure.
• The osmotic pressure of a solution is directly proportional to the solute concentration.
• The basic building blocks of proteins are amino acids.
• DNA is a double-stranded helical structure.
• The monomer unit of nucleic acids is nucleotides.
• Enzymes are biological catalysts that speed up chemical reactions.
• Fats and oils are composed of fatty acids and glycerol.
• The pH scale measures the acidity or basicity of a solution.
• Vitamin C is ascorbic acid.
• ATP is the primary energy currency of cells.
• Carbohydrates are composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio.
• The process of breaking down glucose to produce energy in cells is glycolysis.
• The process of converting light energy into chemical energy in plants is photosynthesis.
• Lipids are insoluble in water due to their hydrophobic nature.
• The main function of red blood cells is to transport oxygen.
• The fluid portion of the blood is called plasma.
• Insulin is produced in the pancreas and regulates blood sugar levels.
• The smallest unit of an element is an atom.
• Water has a higher boiling point compared to oxygen due to stronger intermolecular forces.
• The atomic number of an element is the number of protons in its nucleus.
• Neutrons do not have a charge and contribute to the mass of an atom.
• Isotopes of an element have the same number of protons but a different number of neutrons.
• The periodic table arranges elements based on their atomic number and properties.
• Valence electrons are responsible for the chemical reactivity of an atom.
• Covalent bonds involve the sharing of electrons between atoms.
• The octet rule states that atoms tend to gain, lose, or share electrons to achieve a full outer electron shell.
• The mass number of an atom is the sum of its protons and neutrons.
• The nucleus of an atom contains protons and neutons.
• Mendeleev’s periodic table was arranged based on increasing atomic mass and similar properties.
• The alkali metals are located in Group 1 of the periodic table.
• The halogens are highly reactive nonmetals found in Group 17 of the periodic table.
• Ionic bonds are formed between atoms by transferring electrons.
• Covalent bonds are formed by sharing electrons between atoms.
• Hydrogen has one valence electron and belongs to Group 1 of the periodic table.
• The transition metals are found in Groups 3-12 of the periodic table.
• The noble gases are chemically inert and found in Group 18 of the periodic table.
• The atomic radius generally decreases across a period and increases down a group.
• The first ionization energy is the energy required to remove the outermost electron from an atom.
• Metals tend to lose electrons and form cations, while nonmetals tend to gain electrons and form anions.
• The electronegativity of an element indicates its tendency to attract electrons in a chemical bond.
• A cation is a positively charged ion formed by losing electrons.
• An anion is a negatively charged ion formed by gaining electrons.
• The modern periodic table is arranged based on increasing atomic number and electronic configuration.
• The Lanthanides and Actinides are two series of inner transition metals located at the bottom of the periodic table.
• Metals are typically good conductors of heat and electricity.
• The electron configuration of an element describes the distribution of its electrons in atomic orbitals.
• The atomic number represents the number of protons in the nucleus of an atom.
• The number of protons and electrons is equal in a neutral atom.
• The Aufbau principle states that electrons fill the lowest energy orbitals first.
• Hund’s rule states that electrons occupy degenerate orbitals singly before pairing up.
• Pauli’s exclusion principle states that no two electrons in an atom can have the same set of quantum numbers.
• The s-block and p-block elements are called representative elements.
• The d-block elements are transition metals.
• The f-block elements are lanthanides and actinides.
• The s sublevel can hold a maximum of 2 electrons.
• The p sublevel can hold a maximum of 6 electrons.
• The d sublevel can hold a maximum of 10 electrons.
• The f sublevel can hold a maximum of 14 electrons.
• The electron configuration of an atom is a representation of the distribution of its electrons in different orbitals.
• The valence electrons are the electrons in the outermost energy level of an atom.
• Elements in the same group of the periodic table have similar valence electron configurations and exhibit similar chemical properties.
• A Lewis dot structure represents the valence electrons of an atom using dots.
• Covalent compounds share electrons between atoms to form bonds.
• Ionic compounds form when atoms transfer electrons to achieve full outer shells.
• The oxidation number of an atom indicates the charge it would have in a compound.
• A balanced chemical equation obeys the law of conservation of mass.
• Avogadro’s number (6.022 x 10^23) represents the number of particles in one mole of a substance.
• A mole is a unit used to measure the amount of a substance.
• The molar mass is the mass of one mole of a substance and is expressed in grams per mole.
• Stoichiometry involves calculations based on the balanced chemical equation to determine reactant and product quantities.
• The limiting reactant is the reactant that is completely consumed in a chemical reaction, limiting the amount of product formed.
• The theoretical yield is the maximum amount of product that can be obtained from a given amount of reactants.
• The actual yield is the amount of product obtained in a chemical reaction.
• Percent yield is the ratio of the actual yield to the theoretical yield, multiplied by 100%.
• A homogeneous mixture of two or more substances is a solution.
• The solute is the substance that is dissolved in a solution.
• The solvent is the substance in which the solute is dissolved to form a solution.
• A saturated solution contains the maximum amount of solute that can dissolve at a given temperature.
• An unsaturated solution can dissolve more solute at a given temperature.
• A supersaturated solution contains more solute than is normally possible to dissolve at a given temperature.
• The solubility of a substance is the maximum amount that can dissolve in a solvent at a specific temperature.
• An electrolyte is a substance that dissociates into ions and conducts electricity in a solution.
• A nonelectrolyte is a substance that does not dissociate into ions and does not conduct electricity in a solution.
• Acids are substances that donate protons (H+ ions) in a chemical reaction.
• Bases are substances that accept protons (H+ ions) in a chemical reaction.
• The pH scale measures the acidity or basicity of a solution, ranging from 0 to 14.
• A pH of 7 is neutral, pH less than 7 is acidic, and pH greater than 7 is basic.
• Litmus paper turns red in acidic solutions and blue in basic solutions.
• An indicator is a substance that changes color based on the pH of a solution.
• Strong acids completely dissociate in water to release H+ ions.
• Strong bases completely dissociate in water to release OH- ions.
• The reaction between an acid and a base is called neutralization, producing water and a salt.