Question

the half-life of strontium-90 is approximately 29 years. how much of a 500 g sample of strontium-90 will remain after 58 years​

Answer 1

Explanation:

=500(1+0.5)^2 the final answer is 125

Answer 2

Answer: 125 g

Explanation:

`A = P_o\cdot e^(kt)\\\\\text{First, use the given information to find k:}\\\\\bullet A=(1)/(2)P_o\\\\\bullet k = unknown\\\\\bullet t=29\text{ years}\\\\(1)/(2)P_o=P_o\cdot e^(k(29))\\\\\\(1)/(2)=e^(k(29))\qquad divided\ both\ sides\ by\ P_o\\\\\\ln\bigg((1)/(2)\bigg)=ln\bigg(e^(k(29))\bigg)\qquad applied\ ln\ to\ both\ sides\\\\\\ln\bigg((1)/(2)\bigg)=29k\qquad simplified-ln\ and\ e\ cancel\ out\\\\\\(ln\bigg((1)/(2)\bigg))/(29)=k\qquad divided\ 29\ from\ both\ sides\\\\\\-0.0239=k`

`\text{Now, use the following in the equation to solve for A:}\\\\\bullet A=unknown\\\bullet P_o=500\\\bullet k=-0.0239\\\bullet t=58\text{ years}\\\\A=500\cdot e^((-0.0239)(58))\\\\.\quad=500\cdot e^(-1.386)\\\\.\quad=125`