The concentration CCC (in mg/L) of a bioactive compound in a chemical reactor is modelled by the equation
C=pqt C = pq^t C=pqtwhere ppp and qqq are constants and ttt is the time in hours since the reaction began.
The relationship between ttt and log10C\log_{10} Clog10C is linear. The graph of this relationship passes through the vertical intercept (0,1.48)(0, 1.48)(0,1.48) and the point (25,0.73)(25, 0.73)(25,0.73).
Find an equation for this line in the form log10C=mt+c\log_{10} C = mt + clog10C=mt+c.
Find the value of ppp and the value of qqq, giving your answers to 3 significant figures.
According to the model, find the value of ttt when the concentration reaches 10 mg/L.
Practise Edexcel A Level Maths Regression, Correlation and Hypothesis Testing with exam-style questions for A Level Maths. 202 questions covering Exponential Models, Measuring Correlation, and Hypothesis Testing for Zero Correlation, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
