concentration
Increasing the concentration of reactants will __________ the rate of reaction.
Increase
Which reacts faster with HCl: powdered calcium carbonate or marble chips?
Powdered calcium carbonate
What happens to particle kinetic energy when temperature increases?
Increase
Define catalyst.
A substance that increases rate of reaction without being used up.
Suggest two ways to increase the rate of hydrogen production from Mg + HCl.
Increase acid concentration, use powdered Mg.
Why does higher concentration cause more frequent collisions?
More particles per unit volume.
Why does increasing surface area increase rate of reaction?
More exposed particles for collisions.
Why does higher temperature lead to more effective collisions?
Particles move faster with more energy.
What is the function of a catalyst?
Lowers activation energy.
Which two factors increase the frequency of collisions?
Concentration and surface area.
Give one experiment where concentration affects rate of reaction.
Reaction of sodium thiosulphate with hydrochloric acid.
Farmers use powdered limestone instead of lumps to neutralise soil. Why?
Larger surface area speeds up neutralisation.
Why does food spoil faster at room temperature than in a fridge?
Higher temperature increases rate of decomposition.
Name the catalyst used in the decomposition of hydrogen peroxide.
Manganese(IV) oxide (MnO₂)
Which two factors increase the energy of collisions?
Temperature and catalyst.
Why does reaction slow down as it progresses?
Concentration of reactants decreases.
Name a daily life example where small pieces react faster than large ones.
Powdered sugar dissolves faster in water than a sugar cube.
What happens to reaction rate if temperature is decreased?
Dercrease
Does a catalyst increase the amount of product formed?
No, only increases rate.
In an experiment, doubling the concentration of a reactant doubles the rate of reaction. Explain this observation.
Higher concentration provides more particles per unit volume, causing more frequent effective collisions.
Which solution reacts faster with magnesium ribbon: 1.0 M HCl or 0.5 M HCl?
1.0 M HCl
If 2 g of CaCO₃ is used as powder and as chips, which reacts faster with HCl?
Powder
At higher temperature, more particles have energy __________.
Greater than activation energy
Why are catalysts important in industry?
They save cost and time by speeding up reactions
Factories often increase temperature and use catalysts at the same time. Explain why both are used together.
Higher temperature increases particle energy, while catalyst lowers activation energy, giving maximum reaction speed efficiently.