Question 1

What does reaction rate mean in chemistry?

Accepted Answer

Reaction rate describes how quickly the concentration of a reactant decreases or the concentration of a product increases with time. Concentration is commonly expressed in mol L-1 and time in seconds, giving a concentration-rate unit of mol L-1 s-1.

Question 2

Why are H2, O2 and H2O shown as different symbols in the beaker?

Accepted Answer

The balanced equation is 2H2 + O2 -> 2H2O, so the reactants and product must remain visually distinct. The model shows a packet that consumes two H2 symbols and one O2 symbol while producing two H2O symbols.

Question 3

How is concentration related to particle count in this model?

Accepted Answer

In a fixed vessel, concentration is c = n/V. If every symbol represents the same amount and the volume is fixed, a change in symbol count represents a proportional change in concentration. The visual count is therefore a model of concentration, not a different concentration formula.

Question 4

Which factors affect the rate of a chemical reaction?

Accepted Answer

The important factors include concentration, temperature, pressure for gas reactions, and a catalyst. Temperature can increase particle energy, reducing gas volume can increase concentration, and a catalyst provides an alternative reaction pathway with lower activation energy.

Question 5

Does the order of a reaction come from the balanced equation?

Accepted Answer

No. For a complex reaction, the rate law and order are determined experimentally. Balanced-equation coefficients describe stoichiometric relationships, while the exponents in rate = k[A]^m[B]^n determine the order and are not automatically equal to the stoichiometric coefficients.

Reaction Rate in a 3D Beaker — Stoichiometry & Rate Expression

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