Chemistry Reaction Rates Quiz

False (B)

A substance that increases the speed of a chemical reaction without being consumed in the process.

<p>increase</p> Signup and view all the answers

<p>Measure the amount of product formed = Determine how much gas is produced over time Measure the amount of reactant used = Determine how much material is consumed over time Measure changes in mass = Observe the mass of the reaction mixture over time</p> Signup and view all the answers

<p>The speed of the reaction (B)</p> Signup and view all the answers

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

<p>5 min</p> Signup and view all the answers

<p>used up</p> Signup and view all the answers

<p>The gradient is steepest = The speed of the reaction is fastest The gradient decreases = Reactants being consumed The gradient becomes 0 = No more gas is being produced The reaction has stopped = Speed of reaction = 0</p> Signup and view all the answers

<p>It increases, then levels off (D)</p> Signup and view all the answers

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

<p>The reaction has stopped producing gas.</p> Signup and view all the answers

<p>Color of the reactants (A)</p> Signup and view all the answers

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

<p>activation energy</p> Signup and view all the answers

<p>70</p> Signup and view all the answers

<p>Increase in concentration = Increases effective collisions Increase in temperature = Increases particle energy Presence of a catalyst = Lowers activation energy Increase in pressure = Increases gas particle frequency</p> Signup and view all the answers

<p>Increased frequency of collisions (B)</p> Signup and view all the answers

<p>To lower the activation energy.</p> Signup and view all the answers

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

<p>Size of reacting particles (A)</p> Signup and view all the answers

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

<p>The speed of reaction increases.</p> Signup and view all the answers

<p>250</p> Signup and view all the answers

<p>More collisions occur (D)</p> Signup and view all the answers

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

<p>Temperature, pressure, or concentration.</p> Signup and view all the answers

<p>To increase the reaction speed without being consumed (D)</p> Signup and view all the answers

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

<p>poisons</p> Signup and view all the answers

<p>activation</p> Signup and view all the answers

<p>Catalysts = Remain unchanged after the reaction Enzymes = Proteins that act as biological catalysts Catalysts are selective = Different reactions require different catalysts Enzymes are sensitive = Affected by temperature and pH changes</p> Signup and view all the answers

<p>Decreases the activation energy (A)</p> Signup and view all the answers

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

<p>10</p> Signup and view all the answers

The speed at which a chemical reaction occurs.

The rate of reaction is measured by the amount of reactant used up or the amount of product formed in a given time.

Factors that affect the speed of a reaction, such as temperature, concentration, surface area and catalysts.

A substance that speeds up a reaction without being used up in the process.

Biological catalysts, typically proteins, that speed up biochemical reactions in living organisms.

The steepness of a line on a graph, calculated by dividing the change in the y-axis by the change in the x-axis.

How fast a chemical reaction happens. Measured by how quickly the products are formed or reactants disappear.

The speed of reaction is fastest at the beginning because all reactants are present and available for interaction.

As the reaction proceeds, the concentration of reactants decreases, causing the speed of reaction to slow down.

The speed of reaction reaches zero when the reaction is complete and no more reactants remain.

A graph showing the relationship between the volume of gas produced and the time taken for a reaction.

A graph showing the mass of reactants against time, depicting how the mass changes as the reaction progresses.

A way to measure the reaction rate by observing the change in mass over time. The steepest gradient indicates the fastest reaction.

The minimum amount of energy required for a chemical reaction to occur.

A theory that explains how chemical reactions occur. It states that reactant particles must collide with sufficient energy to break bonds and form new ones.

Increasing the concentration of reactants increases the frequency of collisions between reactant particles, leading to a faster rate of reaction.

Increasing the temperature increases the kinetic energy of reactant particles, making them more likely to collide with sufficient energy to react. This increases the reaction rate.

The volume of gas produced at the end of a reaction is the same, regardless of the time taken. A fast reaction produces the same amount of gas as a slow reaction, but in a shorter time.

Smaller particle size leads to a larger surface area exposed for reactions. This increases the frequency of collisions, resulting in more effective collisions and a faster reaction.

Increasing pressure on gaseous reactants forces particles closer together, increasing their concentration. This leads to more frequent collisions and a faster reaction.

Higher temperature means faster-moving particles with more energy. This increases the likelihood of successful collisions that overcome the activation energy barrier, making the reaction faster.

The minimum energy required for reactants to collide and initiate the reaction.

Reactions involving gases are more likely to be affected by pressure because increasing pressure allows particles to collide more frequently due to increased concentration.

The Haber process is a reaction that produces ammonia from nitrogen and hydrogen gas. It requires high pressure (250 atm) to speed up the reaction.

The reaction between marble (calcium carbonate) and hydrochloric acid, producing carbon dioxide gas.

The larger the surface area of the marble, the more readily it reacts with the acid. Breaking the marble into smaller pieces provides a greater surface area, leading to faster reaction rate.

Catalysts lower the activation energy of a reaction, providing an alternative pathway for it to proceed.

The molecule that an enzyme acts upon.

Enzymes are highly specific, meaning each enzyme works on a specific type of substrate.

Enzymes function best within a narrow range of temperatures.

Enzymes function best within a narrow pH range.