Gas Laws + Collision Theory

What are the properties of gases?

Gases have no definite shape or volume, fill their container, have larger distances between molecules, low density, and are highly compressible.

How is pressure defined in terms of force and area?

Pressure is defined as force divided by area (P = Force / Area).

What device is used to measure atmospheric pressure?

A barometer.

What are the SI units for pressure?

The SI unit of pressure is Pascal (Pa), where 1 Pa = N/m².

What is the relationship between pressure and altitude?

Pressure decreases with altitude due to the lower density of the atmosphere at higher elevations.

What variables can change in a gas contained in a vessel?

Volume (V), Pressure (P), Temperature (T), and Moles (n).

What does Dalton's Law of Partial Pressures state?

In a mixture of gases, the total pressure is the sum of the partial pressures of each individual gas (P_total = P1 + P2 + … + Pn).

What is Boyle's Law?

Boyle's Law states that pressure and volume are inversely related at constant temperature and number of moles (PV = constant).

How does volume affect pressure according to Boyle's Law?

As volume decreases, pressure increases, and as volume increases, pressure decreases.

What does Charles's Law describe?

Charles's Law states that temperature and volume are directly related at constant pressure and number of moles (V/T = constant).

What happens to volume as temperature increases according to Charles's Law?

As temperature increases, volume increases.

What is Gay Lussac's Law?

Gay Lussac's Law states that pressure and temperature are directly related at constant volume and number of moles (P/T = constant).

How does temperature affect pressure according to Gay Lussac's Law?

As temperature increases, pressure increases, and as temperature decreases, pressure decreases.

What does Avogadro's Law state?

Avogadro's Law states that volume and moles of gas are directly related at constant temperature and pressure.

What is the relationship between moles of gas and volume according to Avogadro's Law?

As moles of gas increase, volume increases; as moles of gas decrease, volume decreases.

What is the formula for Boyle's Law?

The formula is P1V1 = P2V2.

What is the formula for Charles's Law?

The formula is V1/T1 = V2/T2.

What is the formula for Gay Lussac's Law?

The formula is P1/T1 = P2/T2.

What is the significance of gas density?

Gases have low density because their molecules are far apart compared to liquids and solids.

How do gas molecules behave in a container?

Gas molecules are constantly bouncing around and colliding with the walls of their container, creating pressure.

What happens to gas pressure when the volume of the container is increased?

The pressure decreases because there is more space for the gas molecules to move, resulting in less frequent collisions.

How does temperature affect the motion of gas molecules?

As temperature increases, gas molecules move faster and spread apart; as temperature decreases, they move less and take up less space.

What is the equation for the relationship between volume (V), number of moles (n), and a constant (k)?

V/n = k

What does the Combined Gas Law combine?

Boyle's, Charles's, Gay-Lussac's, and Avogadro's Laws.

How are pressure and volume related according to the Combined Gas Law?

Pressure and Volume are inversely related.

How are temperature and volume related according to the Combined Gas Law?

Temperature and Volume are directly related.

How are temperature and pressure related according to the Combined Gas Law?

Temperature and Pressure are directly related.

How are moles and volume related according to the Combined Gas Law?

Moles and Volume are directly related.

How are moles and pressure related according to the Combined Gas Law?

Moles and Pressure are directly related.

What does the Ideal Gas Law relate?

Pressure (P), Volume (V), number of moles (n), and Temperature (T) for a single container.

What is the equation for the Ideal Gas Law?

PV = nRT

What is R in the Ideal Gas Law?

R is the ideal gas constant, its value depends on the units used for pressure.

What is the value of R when using liters and atmospheres?

R = 0.0821 L·atm/(mol·K)

What processes occur in a chemical equilibrium?

Reactants convert to products (forward reaction) and products convert to reactants (reverse reaction).

How is chemical equilibrium represented?

Chemical equilibrium is represented using double arrows (⇌).

What does it mean if equilibrium favors products?

It means there are more products than reactants at equilibrium, or it 'lies to the right.'

What does it mean if equilibrium favors reactants?

It means there are more reactants than products at equilibrium, or it 'lies to the left.'

What does it mean if a reaction goes to completion?

It means that all reactants are converted to products.

What is the equilibrium constant (Keq)?

A numerical value indicating the ratio of concentrations of products to reactants at equilibrium.

How is the equilibrium constant (Keq) calculated?

Keq = [Products] / [Reactants].

What does it indicate if Keq > 1?

It indicates that the equilibrium favors products.

What does it indicate if Keq < 1?

It indicates that the equilibrium favors reactants.

What does it indicate if Keq ≈ 1?

It indicates that the concentrations of products and reactants are approximately equal.

What is Le Chatelier's Principle?

If a change is applied to a system in equilibrium, the system will shift to counteract the change and reestablish equilibrium.

How does increasing the concentration of a species affect equilibrium?

The equilibrium will shift to decrease the concentration of that species.

How does decreasing the concentration of a species affect equilibrium?

The equilibrium will shift to increase the concentration of that species.

What happens to equilibrium when temperature is increased in an exothermic reaction?

The equilibrium will shift to the left (endothermic direction) to absorb the added heat.

What happens to equilibrium when temperature is decreased in an exothermic reaction?

The equilibrium will shift to the right (exothermic direction) to produce more heat.

How do pressure changes affect equilibria involving gases?

Increasing pressure shifts equilibrium toward the side with fewer moles of gas; decreasing pressure shifts it toward the side with more moles of gas.

What is the effect of increasing temperature on the rate of reaction?

It increases the rate of reaction, but in equilibrium, it shifts the rate of one reaction more than the other.

In the reaction H2 + I2 ⇌ 2HI, what happens if H2 is added?

The reaction will shift to the right to reduce the amount of H2.

In the reaction N2 + 3H2 ⇌ 2NH3, what happens if pressure is increased?

The reaction will shift to the right to reduce total moles of gas and decrease pressure.

In the reaction N2 + 3H2 ⇌ 2NH3, what happens if pressure is decreased?

The reaction will shift to the left to increase total moles of gas and increase pressure.

What is the relationship between temperature and the equilibrium constant (Keq)?

Temperature is the only factor that changes Keq itself.

What is the significance of equilibrium ratios like 50/50, 20/80, or 80/20?

They indicate the specific concentrations of reactants and products at equilibrium for different reactions.