N1A - Rates of Reaction Flashcards Preview

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Flashcards in N1A - Rates of Reaction Deck (16)
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1
Q

Calculation for average rate of reaction

A

average rate = change in value / time taken

2
Q

What is needed for a reaction to occur

A

the reactant particles need to collide with a certain amount of energy

3
Q

What can be done to increase the number of collisions between reactant particles and the certain amount of energy?

A

increasing the concentration

increasing the surface area

increasing the temperature

adding a catalyst, speeds up reactions without getting used up itself. They can be recovered unchanged at the end of a reaction

4
Q

How can the rate of a reaction be increased?

A

increasing the number of collisions with this energy will speed up a reaction

5
Q

What unit should be used when calculating the rate of reaction when measuring the volume of a gas?

A

cm3s-1

6
Q

How can one tell a reaction has finished on a line graph?

A

The line that is plotted becomes horizontal, indicating that even though time is progressing, there is no increase in the mass of gas that is produced

7
Q

What unit is used in the reaction rate formula

A

gs-1

8
Q

What is the test for CO2?

A

Co2 turns lime water cloudy

9
Q

What is the test for oxygen?

A

oxygen should relight a glowing splint

10
Q

What is the test for hydrogen?

A

hydrogen burns with a pop

11
Q

Why does increasing the concentration of the reactant particle increase the rate of collisions between reactant particles and the certain amount of energy?

A

as there is more reactant particles in a given volume of space

12
Q

Why does increasing the surface area increase the rate of collisions between reactant particles and the certain amount of energy?

A

as more of the reactant particles are exposed

13
Q

Why does increasing the temperature increase the rate of collisions between reactant particles and the certain amount of energy?

A

reactant particles have more energy and more speed so a greater number will collide more often and with greater energy

14
Q

What effect doea increasing the particle size have on the rate on a reaction?

A

As the particle size inceases (i.e. from powder to lumps) the reaction slows down.

15
Q

An experiment to do with gas. During a reaction the mass of the reacting mixture decreases, explain why the mass loss decreased?

A

loss of gas

reaction vessel not sealed so gas can escape thus mass decreases

16
Q

The rate of a reaction decreases with time, explain why.

A

the concentration of reactants decrease

the reactant particles are used up as the reaction proceeds thus the rate of reaction decreases