Interpreting Reaction Rate Graphs

What does the gradient of a reaction graph represent?

The rate of reaction.

What does a steep gradient indicate?

A fast reaction.

What does a shallow gradient indicate?

A slow reaction.

What does a horizontal line on a product-volume graph indicate?

No further product is being formed.

Why does a product-volume graph often become less steep over time?

Reactants are used up, reducing collision frequency.

What does the final plateau of a gas-volume graph show?

The total volume of gas produced.

What does a higher final plateau indicate?

A greater total volume of gas has been produced.

How can two reactions with different rates but the same final gas volume be identified?

Their curves have different gradients but reach the same plateau.

How can two reactions producing different final amounts of gas be identified?

They reach different plateau heights.

How can the fastest reaction be identified from a graph?

It has the steepest initial gradient.

What does a tangent to a curve show?

The gradient at a particular point.

How is instantaneous reaction rate determined from a graph?

By calculating the gradient of a tangent to the curve.

What is the difference between mean rate and instantaneous rate?

Mean rate is calculated over a time interval, while instantaneous rate is measured at a particular moment.

Why is the initial rate often used to compare reactions?

It is measured when reactant concentrations are known and have changed very little.

What does a downward-sloping reactant-mass graph indicate?

The quantity of reactant is decreasing.

Why is the gradient of a reactant-use graph negative?

The amount of reactant decreases with time.

How should a positive rate be obtained from a decreasing-reactant graph?

Use the magnitude of the negative gradient.

Why should graph axes include units?

To make measurements clear and calculations correctly expressed.

What is a common mistake when comparing reaction graphs?

Confusing steeper gradient with greater final yield.