IB skill practice

Use integrated rate relationships and half-life

Paper 1, Paper 2 5 marks Difficulty 5

First-order integrated rate law

A first-order reaction in a Melbourne HL thermochemistry lesson has \([A]_0=0.80\,\text{mol dm}^{-3}\), \(k=0.28\,\text{min}^{-1}\), and \(t=7\,\text{min}\). Calculate \([A]_t\). Enter the answer and choose the interpretation that matches the HL chemistry evidence.

Worked practice: chemistry evidence and answer

Use the chemical evidence first, then enter the result and interpretation that match it.