Chemistry Chapter 11 Quiz

Solids retain their own volume.

Intramolecular interactions are generally stronger.

Intermolecular interactions are broken.

<p>Hydrogen bonding.</p> Signup and view all the answers

<p>Both intermolecular and intramolecular interactions are broken.</p> Signup and view all the answers

<p>The substance that is a liquid at room temperature has stronger intermolecular forces than the substance that is a gas.</p> Signup and view all the answers

<p>Intermolecular forces exist between molecules, whereas intramolecular forces exist within molecules.</p> Signup and view all the answers

<p>Water ($H_2O$) is most likely to be a liquid at room temperature due to its strong hydrogen bonding.</p> Signup and view all the answers

<p>An unsaturated solution.</p> Signup and view all the answers

<p>Molecular solids are held together by the weakest interactions.</p> Signup and view all the answers

<p>Metallic solids are held together by a delocalized 'sea' of collectively shared valence electrons.</p> Signup and view all the answers

<p>The solubility of a gas in a solvent increases with increasing partial pressure of the gas above the solvent.</p> Signup and view all the answers

<p>Substances with similar intermolecular attractive forces tend to be soluble in one another because they can interact favorably, creating a stable solution.</p> Signup and view all the answers

<p>The solubility of most solid solutes in water generally decreases as the temperature increases because the process of dissolving a solid in water is usually an endothermic process.</p> Signup and view all the answers

<p>The solubility of a gas in water generally decreases as the temperature increases because the process of dissolving a gas in water is usually an exothermic process.</p> Signup and view all the answers

<p>Hydrogen bonding</p> Signup and view all the answers

<p>Hydrogen sulfide (H2S) and fluoromethane (CH3F)</p> Signup and view all the answers

<p>Ion-dipole forces occur between an ion and a polar molecule, while dipole-dipole forces occur between two polar molecules.</p> Signup and view all the answers

<p>Viscosity</p> Signup and view all the answers

<p>Viscosity generally decreases with increasing temperature.</p> Signup and view all the answers

<p>Triple point</p> Signup and view all the answers

<p>The critical point represents the highest temperature and pressure at which a liquid can exist, while the triple point is the point where all three phases coexist in equilibrium.</p> Signup and view all the answers

<p>The normal boiling point is the temperature at which a liquid boils at standard atmospheric pressure (1 atm).</p> Signup and view all the answers

<p>It's termolecular because the reaction rate law is third order, meaning the rate is dependent on the concentration of three reactants (A and B in this case).</p> Signup and view all the answers

<p>The overall order of the reaction is three, as the exponents in the rate law add up to three.</p> Signup and view all the answers

<p>Increasing temperature generally increases the rate of chemical reactions.</p> Signup and view all the answers

<p>There is no direct relationship. Order refers to how the rate of a reaction depends on the concentration of reactants, while molecularity describes the number of molecules involved in the elementary step.</p> Signup and view all the answers

<p>The rate law is <code>rate = k[H2][NO]^2</code>.</p> Signup and view all the answers

<p>The units for reaction rates are typically expressed as moles/s.</p> Signup and view all the answers

<p>The frequency factor (A) is related to the rate constant (k) through the Arrhenius equation: <code>k = A * exp(-Ea/RT)</code></p> Signup and view all the answers

<p>The activation energy is the minimum energy required for a reaction to occur. It is the energy difference between the reactants and the transition state. A higher activation energy results in a slower reaction rate since fewer molecules will have enough energy to react.</p> Signup and view all the answers

<p>2.85 °C</p> Signup and view all the answers

<p>The molar mass of the unknown powder can be calculated using the formula ΔTf = Kf * m, where ΔTf is the freezing point depression, Kf is the freezing point depression constant, and m is the molality of the solution. The molality of the solution can be calculated from the mass of the unknown powder and the mass of the ethanol. The molar mass of the unknown powder can then be calculated from the molality and the mass of the unknown powder.</p> Signup and view all the answers

<p>The average rate of disappearance of A is -8.9 × 10^-3 M/min. This is calculated using the formula Rate = -Δ[A]/Δt where Δ[A] is the change in concentration of A and Δt is the change in time.</p> Signup and view all the answers

<p>The reaction rate can be expressed as +3Δ[H2]/Δt. This is because the stoichiometric coefficient of H2 in the balanced chemical equation is 3.</p> Signup and view all the answers

<p>Colligative properties are properties of solutions that depend only on the number of solute particles present, not on their identity. Two examples of colligative properties are freezing point depression and boiling point elevation.</p> Signup and view all the answers

<p>A strong electrolyte is a substance that dissociates completely into ions when dissolved in water, while a weak electrolyte only partially dissociates. A strong electrolyte example is NaCl (sodium chloride), while a weak electrolyte example is CH3COOH (acetic acid).</p> Signup and view all the answers

<p>Reaction rate is the change in concentration of a reactant or product over time. It is measured by monitoring the change in concentration of a species over a specific time interval.</p> Signup and view all the answers

<p>Several factors affect the rate of a chemical reaction, including:</p> <ol> <li> <strong>Concentration:</strong> Increasing the concentration of reactants increases the frequency of collisions, thus increasing the rate. Example: Burning wood burns faster in pure oxygen than in air.</li> <li> <strong>Temperature:</strong> Increasing temperature increases the kinetic energy of molecules, leading to more collisions and a higher rate. Example: Food spoils faster at room temperature than in a refrigerator.</li> <li> <strong>Surface area:</strong> For reactions involving solids, increasing the surface area exposes more reactant molecules, promoting faster reactions. Example: Powdered sugar dissolves faster than sugar cubes.</li> <li> <strong>Catalyst:</strong> A catalyst speeds up the reaction without being consumed, by providing an alternative reaction pathway with lower activation energy. Example: Enzymes in biological systems catalyze reactions.</li> </ol> Signup and view all the answers

<p>0.366 M</p> Signup and view all the answers

<p>0.0164 M</p> Signup and view all the answers

<p>1.23 M</p> Signup and view all the answers

<p>0.432 M</p> Signup and view all the answers

<p>0.332 M</p> Signup and view all the answers

<p>0.860 M</p> Signup and view all the answers

<p>0.311 M</p> Signup and view all the answers

<p>As the temperature decreases, the kinetic energy of the gas molecules decreases and the gas molecules are less likely to escape from the solution. This makes the gas more soluble in water.</p> Signup and view all the answers