Element X is a radioactive isotope such that every 9 years, its mass decreases by half. Given that the initial mass of a sample
of Element X is 70 grams, how long would it be until the mass of the sample reached 56 grams, to the nearest tenth of a year?
1 answer:
Answer:
2.9 years
Step-by-step explanation:
Given that :
Half-life t1/2 = 9 years
Initial mass = I = 70 grams
A = final mass = 56 grams
t = time taken to reach final amount
Using the exponential half life relation :
A = I(0.5)^t/t1/2
56 = 70(0.5)^t/9
56/70 = 0.5^t/9
0.8 = 0.5^t/9
Log 0.8 = log 0.5^t/9
−0.096910 = −0.301029 * t/9
t/9 = 0.096910 / 0.301029
t/9 = 0.3219291
t = 0.3219291 * 9
t = 2.8973619
t = 2.9 years
You might be interested in
Each term is double the one before it, so the appropriate choice is ...
... D. f(x+1) = 2f(x)
Answer:
the correct answer is A
6/5x^10
Step-by-step explanation:
One possible answer is 120°
Answer:
x=3 y=1
Step-by-step explanation:
-x-y=1
y=-x+4
x=-y-1
x=-y+4
x=-1+4
<u>x=3</u>
y=-3+4
<u>y=1</u>
Answer:
Q2. angle 5 +angle 6=90°
angle 5+ 6°=90°
angle 5=90°-6°
angle 5=84°
Q.3 angle 8+angle 9=90°
angle 8 + 11°=90°
angle 8=90°-11°
angle 8=79°
