Chemistry Chapter 5 Quiz

A reaction that releases energy to its surroundings, making the surroundings warmer. Products have less energy than reactants.

A reaction that absorbs energy from its surroundings, making the surroundings cooler. Products have more energy than reactants.

The heat change during a chemical reaction, either absorbed or released.

Negative enthalpy change (ΔH < 0) in an exothermic reaction.

Positive enthalpy change (ΔH > 0) in an endothermic reaction.

The tendency of a system to have lower energy content.

Diagram showing relative energy levels of reactants and products in a reaction.

The total energy content of a substance.

A state where a substance does not react quickly even though it has a high energy level.

The minimum amount of energy needed for a reaction to start.

Determining the heat energy released or absorbed during a reaction by measuring temperature changes.

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

Using the formula: ∆H = (mc∆T) / n, where m is mass, c is specific heat capacity, ∆T is temperature change, and n is moles.

Assuming the density of aqueous solutions is 1 g/cm³ and their specific heat capacity is the same as water.

The heat change when an acid and a base react to form salt and water.

The heat change when a substance reacts with oxygen to produce energy.

When ions dissolve, ion-solvent bonds form. The stability of this process depends on whether the energy released from forming these bonds outweighs the energy needed to break the initial ionic and solvent-solvent bonds.

Polar molecules have a natural attraction to ions, allowing them to dissolve effectively. The energy released from forming ion-solvent bonds compensates for the energy required to break strong ionic bonds.

Covalent compounds dissolve well in non-polar solvents as the energy released from forming molecule-solvent bonds is enough to overcome the weak van der Waals forces between covalent molecules.

Covalent compounds often do not dissolve in polar solvents. The energy required to break the strong forces within polar solvents is too high, making the dissolution process unstable.

Certain covalent compounds react chemically with water rather than dissolving. This reaction forms ions, which are then soluble.

Metals generally do not dissolve in either polar or non-polar solvents. However, some reactive metals like sodium and calcium can react with water.

The kinetic theory of gases describes an ideal gas. It assumes that gas particles have negligible volume, no intermolecular forces, and move randomly with elastic collisions.

The ideal gas model breaks down at very high pressures and very low temperatures. At high pressure, the gas molecules are close, increasing intermolecular forces and volume. At low temperatures, the molecules move slower, making intermolecular forces more significant.