Which of these statements is not true regarding reaction rate?

a. increasing particle size increases reaction rate.
b. raising the temperature increases reaction rate.
c. adding a catalyst increases reaction rate.
d. increasing concentration of the of reactants increases rate.

These questions are based on the attached photo. the experiment is about burning magnesium metal with oxygen. 1. write the balanced chemical equation for the reaction you are performing. 2. calculate the mass of magnesium metal used in each trial. o trial 1: o trial 2: 3. calculate the actual yield of magnesium oxide for each trial. o trial 1: o trial 2: 4. magnesium is the limiting reactant in this experiment. calculate the theoretical yield of mgo for each trial. o trial 1: o trial 2: 5. determine the percent yield of mgo for your experiment for each trial. o trial 1: o trial 2: 6. determine the average percent yield of mgo for the two trials. your company currently uses a process with a similar cost of materials that has an average percent yield of 91 percent. if the average percent yield of this process is higher than that, this could save the company money. what is your recommendation to the company? support your recommendation using your data, calculations, and understanding of stoichiometry gathered from this lab.

State one important difference between a physical change and a chemical change?

Quickly what are the following of organisms that existed over a wide area but only for a limited time period called a. soft fossils b. mold fossils c. index fossils d. trace fossils