The half-life of a substance is 6.
At time = 0, this substance has size 80. Calculate the size of the substance at time = 18
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The half-life of a substance is 6
At time = 0, this substance has size 80
Calculate the size of the substance at time = 18
Step 1: Calculate Time Difference (Δ)
Δ = tn - t
Δ = 18 - 0
Δ = 18
Step 2: Calculate number of half-lives (hn)
hn =
Δ
h
hn =
18
6
hn = 3 <-- Number of times we will reduce our original size by ½
Step 3: Calculate New Substance Size (xn)
We go through each time starting at t = 0 all the way to hn = 3
Substance size at time = 1
x1 = ½(x0)
x1 = ½(80)
x1 = 40
Substance size at time = 2
x2 = ½(x1)
x2 = ½(40)
x2 = 20
Substance size at time = 3
x3 = ½(x2)
x3 = ½(20)
x3 = 10
Shortcut Solution to Above
xn = ½hnx0
xn = ½3(80)
xn =
80
8
xn = 10
You have 2 free calculationss remaining
What is the Answer?
xn = 10
How does the Half-Life of a Substance Calculator work?
Free Half-Life of a Substance Calculator - Given a half-life (h) of a substance at time t, this determines the new substance size at time tn, otherwise known as decay. This calculator has 4 inputs.
What 4 formulas are used for the Half-Life of a Substance Calculator?
Δ = tn - t Number of half lives = Δ/half life Half Life Remaining = 1/2 * Prior Amount