Calorimetry and Heat Capacity Quiz

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which property describes the effect of solution concentration on boiling point elevation?

  • Vapor pressure lowering
  • Chemical reactivity
  • Freezing point depression
  • Colligative properties (correct)

What is the primary use of a eudiometer in chemical experiments?

  • To track temperature changes
  • To analyze gas composition (correct)
  • To quantify colligative properties
  • To measure vapor pressure

In accordance with the Ideal Gas Law, what happens to gas pressure if volume decreases while temperature remains constant?

  • Pressure decreases
  • Pressure remains constant
  • Pressure becomes negative
  • Pressure increases (correct)

Which of the following statements is true regarding Boyle's Law?

<p>As volume increases, pressure decreases (C)</p> Signup and view all the answers

Charles' Law states that volume and temperature of a gas are related how?

<p>Directly proportional at constant pressure (B)</p> Signup and view all the answers

What factor does not affect the colligative properties of a solution?

<p>Nature of solute (B)</p> Signup and view all the answers

What occurs to a gas when both its pressure and volume decrease? Assuming temperature remains constant.

<p>Gas compresses (D)</p> Signup and view all the answers

Which law describes the relationship between the volume of a gas and its absolute temperature at constant pressure?

<p>Charles' Law (C)</p> Signup and view all the answers

In chromatography, what is the primary reason for the separation of compounds in a mixture?

<p>Differences in solubility and adsorption (C)</p> Signup and view all the answers

What is the primary factor that affects the polarity of a molecule?

<p>Electronegativity of atoms (B)</p> Signup and view all the answers

In normal phase chromatography, what characterizes the stationary phase?

<p>Polar material (A)</p> Signup and view all the answers

The retention factor (Rf) in chromatography relates to what aspect of the compounds?

<p>Their solubility and polarity (B)</p> Signup and view all the answers

The stationary phase in paper chromatography is typically made of which material?

<p>Cellulose (D)</p> Signup and view all the answers

Which of the following intermolecular forces is the strongest?

<p>Ion-ion attractions (A)</p> Signup and view all the answers

In reverse phase chromatography, the stationary phase is characterized as being:

<p>Nonpolar (B)</p> Signup and view all the answers

Which principle suggests that a system will counteract the changes to regain equilibrium?

<p>Le Chatelier's Principle (A)</p> Signup and view all the answers

What ensures that the chromatography system remains saturated during the run?

<p>Saturation filter paper (C)</p> Signup and view all the answers

Which of these describes a characteristic of hydrogen bonding?

<p>Is a stronger force than London dispersion forces (C)</p> Signup and view all the answers

Which statement accurately describes the relationship between carbon content and polarity?

<p>Higher carbon content results in more nonpolar substances. (D)</p> Signup and view all the answers

What happens when NH4Cl is dissolved in water?

<p>It absorbs heat and is endothermic. (C)</p> Signup and view all the answers

Which of the following best describes the process of distillation?

<p>Separation based on differing boiling points of liquids. (C)</p> Signup and view all the answers

Which scenario describes an exothermic reaction in the context of dissolution?

<p>Dissolving Ca(OH)2 in water. (C)</p> Signup and view all the answers

When the temperature rises in a dissolution reaction, what is the expected effect on the solubility of a solid solute?

<p>Solubility increases for endothermic reactions. (A)</p> Signup and view all the answers

What type of distillation is used to separate liquids with boiling points differing by less than 25 °C?

<p>Fractional distillation (D)</p> Signup and view all the answers

Which combination of solutions would be considered miscible?

<p>Ethanol and water (A)</p> Signup and view all the answers

What is the effect of pressure on a reaction mixture where there are fewer gas molecules on the product side?

<p>More product will be formed with increased pressure. (A)</p> Signup and view all the answers

In a solution of I2 and KI in water, what phenomenon is observed?

<p>A color change indicates the formation of I3-. (C)</p> Signup and view all the answers

Flashcards

Calorimetry

Measuring heat absorbed or released during a chemical reaction.

1st Law of Thermodynamics

Energy is conserved; it cannot be created or destroyed, only transformed.

Constant Pressure Calorimetry

Measures heat changes at constant pressure using a coffee cup or styrofoam calorimeter.

Adiabatic System

A system where no heat is transferred to or from the surroundings.

Signup and view all the flashcards

Heat Capacity (C)

The amount of heat required to raise the temperature of a substance by 1 degree Celsius.

Signup and view all the flashcards

Endothermic Reaction

A reaction that absorbs heat from the surroundings.

Signup and view all the flashcards

Exothermic Reaction

A reaction that releases heat to the surroundings.

Signup and view all the flashcards

Chromatography

A technique for separating mixtures based on different properties.

Signup and view all the flashcards

Mobile Phase

The moving fluid in chromatography that carries the components through the stationary phase.

Signup and view all the flashcards

Stationary Phase

The fixed material in chromatography that interacts with the components of the mixture.

Signup and view all the flashcards

Polarity

A measure of the uneven distribution of electrons within a molecule, creating partial positive and negative charges.

Signup and view all the flashcards

Like Dissolves Like

A principle stating that polar substances dissolve in polar solvents, and nonpolar substances dissolve in nonpolar solvents.

Signup and view all the flashcards

Intermolecular Forces (IMFA)

Attractive forces between molecules that affect their physical properties, such as melting point and boiling point.

Signup and view all the flashcards

Normal Phase Chromatography

A chromatography technique where the stationary phase is polar, and the mobile phase is nonpolar.

Signup and view all the flashcards

Reverse Phase Chromatography

A chromatography technique where the stationary phase is nonpolar, and the mobile phase is polar.

Signup and view all the flashcards

Retention Factor (Rf)

A measure of how strongly a component interacts with the stationary phase, indicating its relative mobility in the mobile phase.

Signup and view all the flashcards

Le Chatelier's Principle

A principle stating that when a change is applied to a system at equilibrium, the system will shift in a direction that relieves the stress.

Signup and view all the flashcards

Solubility: Polar vs Nonpolar

Polar solutes dissolve in polar solvents (like dissolves like). Nonpolar solutes dissolve in nonpolar solvents. Polar and nonpolar substances are generally immiscible.

Signup and view all the flashcards

Solubility: Effect of Intermolecular Forces

Stronger intermolecular forces between solute and solvent molecules lead to higher solubility.

Signup and view all the flashcards

Solubility: Effect of Temperature

Endothermic reactions: Higher temperature increases solubility. Exothermic reactions: Lower temperature increases solubility.

Signup and view all the flashcards

Solubility: Effect of Concentration

Increasing concentration of reactants favors the forward reaction. Increasing concentration of products favors the reverse reaction.

Signup and view all the flashcards

Distillation: Simple

Separating miscible liquids by boiling point difference when one liquid is nonvolatile.

Signup and view all the flashcards

Distillation: Vacuum

Separating liquids with high boiling points by reducing pressure to lower the boiling point.

Signup and view all the flashcards

Distillation: Fractional

Separating liquids with similar boiling points by using a fractionating column.

Signup and view all the flashcards

Distillation: Steam

Separating liquids insoluble or slightly soluble in water by co-distilling with steam.

Signup and view all the flashcards

Distillation: Miscible vs Immiscible

Distillation separates miscible liquids, which have components mixed together in any proportion, by boiling point differences. Immiscible liquids, which don't mix, can usually be separated by physical means like decantation.

Signup and view all the flashcards

Distillation: Process

The solution is heated in a distilling flask, vapors rise, condense in a condenser, and the distillate is collected.

Signup and view all the flashcards

Study Notes

Calorimetry

  • Calorimetry is the process of measuring the amount of heat released or absorbed during a chemical reaction.
  • The first law of thermodynamics states that the total internal energy of the universe is constant; energy cannot be created or destroyed, only converted.
  • The law of conservation of energy states that the universe acts as an isolated system.
  • Types of calorimetry include constant pressure calorimetry (coffee cup or styrofoam calorimeter) and constant volume calorimetry (bomb calorimeter).
  • An adiabatic system does not transfer heat to its surroundings.

Heat Capacity

  • Heat capacity is the tendency for a substance to absorb or release heat.
  • qrxn + qcal = 0
  • qrxn = -qcal
  • qrxn = (ΔHrxn)(nLR)
  • qcal = CcalΔT
  • If ΔH is positive, it is endothermic (heat is absorbed); if negative, it is exothermic (heat is released).

Calibration

  • Calibration determines the heat capacity of the calorimeter.
  • The heat capacity of a calorimeter is not constant, and it must be calibrated for each calorimeter or set of conditions.
  • ΔHrxn of HCl + NaOH → NaCl + H2O = -55.85 kJ/mol

Chromatography

  • Chromatography is a separation technique for a mixture.
  • Chroma + graphein = to illustrate/write color
  • Developed by Mikhail Tsvet.
  • Types of chromatography include paper chromatography, column chromatography, and thin-layer chromatography (TLC).

Paper Chromatography

  • Separation happens because there are competing factors: attraction to the solvent (mobile phase) and the paper (stationary phase).

Intermolecular Forces of Attraction (IMFA)

  • Separation is based on polarity.
  • Polarity is determined by: electronegativity of atoms, geometry
  • IMFA are arranged in order of decreasing strength:
    • Ion-ion
    • Ion-dipole
    • Hydrogen bonding
    • Dipole-dipole
    • Ion-induced dipole
    • Dipole-induced dipole
    • London dispersion forces

Determination of ∆Hrxn

  • ∆Hrxn = (Ccal)(ΔT) ÷ nLR

Dynamic Equilibrium

  • When the rate of the forward reaction equals the rate of the reverse reaction, a system is in dynamic equilibrium.

Le Chatelier's principle

  • If a dynamic equilibrium is disturbed, the system will react to counteract the change and attain new equilibrium.

Types of Equilibria

  • Acids-base
  • Solubility
  • Color changes can be observed in acid and base reactions (natural indicators)

Effect of nature of solvent and solute

  • Nature of the solute and solvent determines their miscibility (ability to mix).
  • Polar solutes mix with polar solvents; nonpolar solutes mix with nonpolar solvents.
  • Nonpolar solvents and polar solvents are immiscible.

Distillation

  • Distillation is used to separate miscible liquids based on boiling point differences among substance components.
  • Types include simple distillation, vacuum distillation, fractional distillation, and steam distillation.

Gas Laws

  • Boyle's Law: P1V1 = P2V2 (constant T)
  • Charles' Law: V1/T1 = V2/T2 (constant P)
  • Gay-Lussac's Law: P1/T1 = P2/T2 (constant V)
  • Combined Law: P1V1/T1 = P2V2/T2
  • Ideal Gas Law: PV = nRT

Eudiometer

  • An instrument to measure gas volume.
  • Three different formulas apply to different scenarios.

Colligative Properties

  • Boiling point elevation (BPE)
  • Freezing point depression (FPD)
  • Vapor pressure lowering (VPL)
  • Osmotic pressure (OP)
  • These properties depend on the concentration of solute (not the identity of the solute), not the properties of the solute.

pH, Conductivity, and Relative Strengths of Acids/Bases

  • Arrhenius definition: Acids dissociate to produce H+ ions, and bases dissociate to produce OH− ions.
  • Brønsted-Lowry definition: Acids are proton donors, and bases are proton acceptors.
  • Lewis definition: Acids are electron-pair acceptors, and bases are electron-pair donors.

Conductivity Test

  • Strong acids/bases are strong electrolytes (conduct electricity well).
  • Weak acids/bases are weak electrolytes (conduct electricity poorly).
  • Concentration and dilution affect conductivity

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

CHEM 16.1 REVIEWER PDF

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser