The half-life of a substance is 1.
At time = 0, this substance has size 100. Calculate the size of the substance at time = 7
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The half-life of a substance is 1
At time = 0, this substance has size 100
Calculate the size of the substance at time = 7
Step 1: Calculate Time Difference (Δ)
Δ = tn - t
Δ = 7 - 0
Δ = 7
Step 2: Calculate number of half-lives (hn)
hn =
Δ
h
hn =
7
1
hn = 7 <-- 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 = 7
Substance size at time = 1
x1 = ½(x0)
x1 = ½(100)
x1 = 50
Substance size at time = 2
x2 = ½(x1)
x2 = ½(50)
x2 = 25
Substance size at time = 3
x3 = ½(x2)
x3 = ½(25)
x3 = 12.5
Substance size at time = 4
x4 = ½(x3)
x4 = ½(12.5)
x4 = 6.25
Substance size at time = 5
x5 = ½(x4)
x5 = ½(6.25)
x5 = 3.125
Substance size at time = 6
x6 = ½(x5)
x6 = ½(3.125)
x6 = 1.5625
Substance size at time = 7
x7 = ½(x6)
x7 = ½(1.5625)
x7 = 0.78125
Shortcut Solution to Above
xn = ½hnx0
xn = ½7(100)
xn =
100
128
xn = 0.78125
You have 2 free calculationss remaining
What is the Answer?
xn = 0.78125
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