Please, even if you only know one, please answer.
1. What are the four factors that affect the rate of reaction?
2. Describe three different ways of measuring the rate of a reaction. Give one advantage and one disadvantage of each method.
3. A student carries out an experiment to measure the effect of surface area on the reaction between marble and hydrochloric acid. He measures the mass of gas given off at regular intervals.
He uses four samples for his experiment:
Sample A: 10g of powdered marble
Sample B: 10g of small marble chips
Sample C: 10g of large marble chips
Sample D: 5g of powdered marble
Sketch a typical set of graphs for this experiment, with time on the horizontal axis and mass of gas evolved on the vertical axis (just help on this one).
4. Explain how the frequency of collisions between particles is increased by:
a) increasing the temperature
b) using more concentrated solutions
c) increasing the surface area of the reactants
1. What are the four factors that affect the rate of reaction?
2. Describe three different ways of measuring the rate of a reaction. Give one advantage and one disadvantage of each method.
3. A student carries out an experiment to measure the effect of surface area on the reaction between marble and hydrochloric acid. He measures the mass of gas given off at regular intervals.
He uses four samples for his experiment:
Sample A: 10g of powdered marble
Sample B: 10g of small marble chips
Sample C: 10g of large marble chips
Sample D: 5g of powdered marble
Sketch a typical set of graphs for this experiment, with time on the horizontal axis and mass of gas evolved on the vertical axis (just help on this one).
4. Explain how the frequency of collisions between particles is increased by:
a) increasing the temperature
b) using more concentrated solutions
c) increasing the surface area of the reactants
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1:
Temperature
Concentration
Surface Area
Presence of a catalyst
Of those I am 100% SURE.
4:
Temperature goes up, speed of particles goes up. Therefore there are more collisions, and harder collisions. Collisions have to have enough force (and be at the right angle) to be successful, and obviously if the frequency of collisions is raised so is the frequency of successful collisions.
Water is not a reactant. It gets in the way of the reactants, lowering the number of collisions. Less collisions means less successful collisions, less successful collisions means slower reaction time.
With more surface area, there are more particles available to react. For an analogy, compare dissolving a cube of sugar in water to dissolving loose sugar in water. The loose powder dissolves faster, because unlike in the cube,no particles are blocked away and hidden by other particles. More surface area, more collisions... you know the drill.
Temperature
Concentration
Surface Area
Presence of a catalyst
Of those I am 100% SURE.
4:
Temperature goes up, speed of particles goes up. Therefore there are more collisions, and harder collisions. Collisions have to have enough force (and be at the right angle) to be successful, and obviously if the frequency of collisions is raised so is the frequency of successful collisions.
Water is not a reactant. It gets in the way of the reactants, lowering the number of collisions. Less collisions means less successful collisions, less successful collisions means slower reaction time.
With more surface area, there are more particles available to react. For an analogy, compare dissolving a cube of sugar in water to dissolving loose sugar in water. The loose powder dissolves faster, because unlike in the cube,no particles are blocked away and hidden by other particles. More surface area, more collisions... you know the drill.
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