measuring reaction rates

Question 1

how to measure rates of reaction

Answer 1

if a reaction produces gas, you can easily measure the reaction rate by collecting gas in ages syringe and recording how much is collected each second.

Question 2

what is the danger of fine powders in a flour mill?

Answer 2

flour particles have a large surface area. If there is a lot of flour dust in the air, a spark from the machine is enough to cause a reaction between the flour and the spark to form an explosion

Question 3

what is the danger of fine gases in coal mines

Answer 3

There are all sorts of flammable gases in the air. At the right concentration, these gases form an explosive mix with the air. this is enough to set off an explosion

Question 4

how to interpret data from experiments concerned with rates of reaction

Answer 4

both experiments produce the same amount of product. The fastest one to finish reacting is the one with the quickest rate of reaction

Question 5

equation for average rate of reaction

Answer 5

average rate of reaction = total produced/ time taken

Question 6

define collision theory

Answer 6

when molecules collide bonds between their atoms can break and then new bonds can form to make new molecules. Particles can only react with each other when they collide.

Question 7

what is activation energy

Answer 7

the minimum energy needed for particles to react when they collide.

Question 8

oxidisation

Answer 8

the gain of oxygen, loss of electrons

Question 9

reduction

Answer 9

the loss of oxygen, gain of electrons

Question 10

what is a redox reaction

Answer 10

a reaction where oxidisation and reduction occur together

Question 11

electron transfer in redox reactions

sodium reacting with chlorine

Answer 11

in this reaction sodium loses an electron
the sodium has been oxidised because the sodium atom has lost an electron
each chlorine atom in the chlorine molecule gains one electron.
the chlorine has been reduced because each chlorine atom has gained an electron