Chemistry Reaction Rates Overview

Temperature, concentration, surface area, catalyst (such as enzymes)

Higher temperatures mean there is more energy therefore the particles move faster and collide more often and more violently.

Increased concentration of the reactants means there are more particles in the same volume therefore more collisions occur each second.

<p>Increased surface area increases the number of particles of the solid in contact with the other reactant in solution increasing the number of particle collisions.</p> Signup and view all the answers

<p>Catalysts are substances that increase the rate of reactions without being used up in the process. Catalysts speed up reactions by providing an alternative pathway with lower activation energy for the reactants.</p> Signup and view all the answers

<p>Enzymes are biological catalysts which work best under certain conditions of temperature and pH. Other conditions can lead to them being denatured.</p> Signup and view all the answers

<p>The minimum amount of energy needed to break the initial bonds in the reactants for a chemical reaction to take place.</p> Signup and view all the answers

<p>When particles react with enough energy and correct orientation for bonds to be broken.</p> Signup and view all the answers

<p>A fast reaction.</p> Signup and view all the answers

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

<p>The speed of a reaction: how fast the products are formed from the reactants.</p> Signup and view all the answers

<p>The reactant not in excess that stops the reaction when it is used up.</p> Signup and view all the answers

<p>Salt dissolving in water and combustion of magnesium.</p> Signup and view all the answers

<p>Photosynthesis and electrolysis.</p> Signup and view all the answers

<p>Amount of reactant or amount of product divided by time.</p> Signup and view all the answers

<p>CaCO3(s) + 2HCl(aq) -&gt; CaCl2(aq) + H2O(l) + CO2(g)</p> Signup and view all the answers

<p>Measure out x amount of hydrochloric acid and leave it in the measuring cylinder. Measure out x amount of sodium thiosulphate solution and pour it into a conical flask, heating it to X degrees with either a Bunsen burner or water bath using a thermometer to measure temperature. When the temperature has reached X, take the flask off the heat and put it onto a piece of paper with an X drawn on it. Pour the acid into the flask and time how long it takes for the X to disappear with a stopwatch. Repeat the investigation at 3 other temperatures to test the rates at different temperatures.</p> Signup and view all the answers

<p>1/time taken.</p> Signup and view all the answers

<p>Add 273.</p> Signup and view all the answers

<p>Rate dramatically increases with temperature.</p> Signup and view all the answers

<p>The particles move faster as they have more energy. This means the frequency of collisions increases. There are more collisions of the correct orientation and amount of activation energy; therefore, more particles possess activation energy and more successful collisions occur.</p> Signup and view all the answers

<p>Filter the residue and the catalyst will catch in the filter paper - insoluble solid.</p> Signup and view all the answers

<p>Manganese dioxide.</p> Signup and view all the answers

<p>2H2O2 -&gt; (MnO2) -&gt; 2H2O + O2.</p> Signup and view all the answers

<p>To save money as many substances have very high activation energy.</p> Signup and view all the answers