Question

A scientist is doing an experiment with a chemical that has a half-life of 11 days. How much of the chemical will be remaining after 40 days if there were 300 grams at the beginning of his lab?

Answer 1

the formula for half life is \[\frac{\ln 2}{k} = t\]
so \[k = \frac{\ln 2}{t}\]
\[\implies k = \frac{\ln 2}{11}\]
\[\implies k = 0.0630\]
to find how much there would be after 40 days use the exponential decay formula \[x = x_o e^{-kt}\]
\[\implies x = (300)(e)^{-0.0630 \times 40}\]
\[\implies x = (300)e^{-2.52}\]
\[\implies x = (300)(0.0805)\]
\[\implies x = 24.14\]
\[\implies x \approx 25\]
does that help?

Answer 2

yes thanks

Answer 3

welcome