Lo 11 (topic 1) Flashcards
What is the rate of a chemical reaction?
The rate of a chemical reaction is an indication of how rapidly the reactants are changed into products or the products into reactants.
How can the rate of a chemical reaction be defined?
The rate of a chemical reaction can be defined as: (change in concentration) / (time taken).
What are some methods to measure the rate of a chemical reaction?
Methods include using a stopwatch to measure time taken for signs of a reaction such as color change or formation of gas.
What equipment can be used to monitor the rate of reaction by recording the volume of gas given off at regular intervals?
gas syringe or an upside-down measuring cylinder/burette can be used.
What are some experiments done to investigate how the surface area affects the rate of reaction?
1)React Mg turning then Mg powder with HCl( collect hydrogen produced)
2) React HCl with large marble chips and then with small marble chips( use a weighing scale)
What are some experiments done to determine the rate of reaction?
1)Reaction between an acid and sodium thiosulfate( watch the solution turn from colour less to cloudy)
2) Reaction between an acid and different metals ( collect the hydrogen)
3)Reaction between limestone and an acid(use a weighing scale)
What is the chemical equation for the reaction between calcium carbonate and hydrochloric acid?
CaCO3 + 2HC1 → CaCl + H20 + CO2
How can the rate of reaction be monitored in the experiment involving hydrochloric acid and calcium carbonate?
The rate of reaction can be monitored by recording the volume of carbon dioxide given off at regular intervals.
What are the reactants in the reaction between sodium thiosulfate and hydrochloric acid?
Sodium thiosulfate (Na,S,03) and hydrochloric acid (HCI).
What are the products of the reaction between sodium thiosulfate and hydrochloric acid?
Sulfur (S), sodium chloride (NaCl), water (H20), and sulfur dioxide (SOz).
What is the visual indicator used to measure the reaction rate in the sodium thiosulfate and hydrochloric acid experiment?
The disappearance of a black cross placed underneath the conical flask.
What is the method to start the reaction between sodium thiosulfate and hydrochloric acid?
Add 50 cm’ of sodium thiosulfate solution to a conical flask, place it on a paper with a black cross, add 10 cm of hydrochloric acid, swirl to mix, and start a stop clock.
What is Collision Theory?
A theory that explains how chemical reactions occur and why rates differ; it states that molecules must collide with sufficient energy to break bonds.
What factors affect reaction rates according to Collision Theory?
State of subdivision, concentration, temperature, and pressure.
What is required for a collision between reactants to be successful?
Reactants must collide with correct orientation and sufficient energy to break existing bonds and form new ones.
What does an energy profile graph show in a chemical reaction?
illustrates the progress of reaction including activation energy needed for reactants and heat released during product formation.
What is the main reaction in the experiment between limestone and acid( HCl)?
The reaction between limestone (calcium carbonate) and hydrochloric acid produces calcium chloride, water, and carbon dioxide gas.
What are the steps to set up the experiment between calcium carbonate and HCl ?
- Transfer a known volume of acid to a conical flask.
- Add a few grains of limestone.
- Place a bung with a delivery tube on top and collect the gas.
How is the reaction rate monitored in this experiment between calcium carbonate and hydrochloric acid?
By noting the mass on the digital weighing scale every 30 seconds and recording it on a table
What happens to the rate of a reaction involving gases when the pressure is increased?
The rate of a reaction involving gases increases when the pressure is increased.
Does the change in pressure affect the reaction rates of solids and liquids?
No, the reaction rates of solids and liquids remain unaffected by changes in pressure.
According to collision theory, why does increasing the pressure of a gas increase the rate of reaction?
Increasing the pressure of a gas increases the rate of reaction because it leads to a higher number of collisions between gas particles.
What is the result of compressing a gas into a smaller volume?
Compressing a gas into a smaller volume increases its pressure, leading to more collisions with the walls of the container.
How does the concentration of reactant gases in a given volume relate to the pressure?
The higher the pressure, the higher the concentration of reactant gases in a given volume, resulting in an increased rate of reaction.
