chemical industry (CI) Flashcards
(31 cards)
What is the definition of reaction rate?
The reaction rate is the change in the amount of reactants or products per unit time.
Name four ways to measure the rate of a reaction.
pH measurement, gas volume, loss of mass, colour change.
How can the rate of reaction be determined from a concentration-time graph?
The rate of reaction at any given point can be determined by drawing a tangent to the curve at that point and calculating its slope.
What is the initial rate of a reaction?
The initial rate is the rate of reaction at the start, calculated as the amount of reactant used or product formed per unit time.
What are clock reactions?
Clock reactions measure the time it takes for a set amount of product to be formed as concentration changes.
What is the rate equation?
The rate equation expresses the rate of a reaction as a function of the concentration of reactants, with a rate constant (k) that is specific for a given reaction at a given temperature.
What is the rate constant (k)?
The rate constant (k) is a proportionality constant in the rate equation that depends on the temperature and the specific reaction.
What does order 0 mean in terms of reaction rate?
In a zero-order reaction, the rate of the reaction is independent of the concentration of the reactant.
What does first order mean in terms of reaction rate?
In a first-order reaction, the rate is directly proportional to the concentration of the reactant.
What does second order mean in terms of reaction rate?
In a second-order reaction, the rate is proportional to the square of the concentration of the reactant.
What happens to the half-life of a reactant in a zero-order reaction?
In a zero-order reaction, the half-life decreases as time progresses.
What happens to the half-life of a reactant in a first-order reaction?
In a first-order reaction, the half-life remains constant.
What happens to the half-life of a reactant in a second-order reaction?
In a second-order reaction, the half-life increases as time progresses.
What is the Arrhenius equation?
The Arrhenius equation, k = Ae^(-Ea/RT), links the rate constant (k) with the activation energy (Ea), the temperature (T), and a constant (A).
What does the activation energy (Ea) represent in the Arrhenius equation?
The activation energy (Ea) represents the minimum energy required for reactants to undergo a successful collision and form products.
What is dynamic equilibrium?
Dynamic equilibrium occurs when the rates of the forward and reverse reactions are equal, resulting in a constant ratio of products to reactants.
How does temperature affect the equilibrium constant (Kc)?
Increasing the temperature favors the endothermic direction of the reaction, causing a shift in equilibrium and potentially changing the value of Kc.
What are the conditions used in the Haber process?
The Haber process uses a temperature of 400°C and a pressure of 200 atm to produce ammonia from nitrogen and hydrogen.
How are equilibrium concentrations measured experimentally?
Colorimetry: Measure the absorbance of a colored substance at equilibrium and compare it with a calibration curve. pH measurement: Use a pH probe if the reaction involves acidic or basic components.
What is the electronic configuration of nitrogen?
The electronic configuration of nitrogen is 1s² 2s² 2p³, with 5 outer shell electrons.
What are the properties of ammonia?
Ammonia (NH₃) has one lone pair and can form hydrogen bonds, making it very soluble in water.
How do ammonium ions behave in coordination chemistry?
Ammonium ions (NH₄⁺) can act as ligands by forming dative covalent bonds with transition metals.
What are the common nitrogen oxides?
NO (nitrogen monoxide): Colorless gas. N₂O (dinitrogen monoxide): Colorless gas, sweet smell. NO₂ (nitrogen dioxide): Brown gas, toxic, sharp odor.
How do you test for ammonium compounds?
Add sodium hydroxide (NaOH). Ammonia gas is released, which turns damp red litmus paper blue, indicating alkalinity.
