Answer:
ummm what is that give me more detail please
The trajectory of their motion knocked the Earth into a different orbit.
The thid choice (from left to right) is a Ball and Stick Model.
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Answer:</h3>
#1. 50 g
#2. 25 g
#3. 4 half lives
<h3>
Explanation:</h3>
<u>We are given;</u>
- Original mass of a radioisotope as 100 g
- Half life of the radioisotope as 10 years
We need to answer the questions:
#a. Mass remaining after 10 years
Using the formula;
Remaining mass = Original mass × 0.5^n , where n is the number of lives.
In this case, since the half life is 10 years then n is 1
Therefore;
Remaining mass = 100 g × 0.5^1
= 50 g
Therefore, 50 g of the isotope will remain after 10 years
#b. Mass of the isotope that will remain after 20 years
Remember the formula;
Remaining mass = Original mass × 0.5^n
n = Time ÷ half life
n = 20 years ÷ 10 years
= 2
Therefore;
Remaining mass = 100 g × 0.5^2
= 25 g
Thus, 25 g of the isotope will be left after 20 years
#3. Number of half lives in 40 years
1 half life = 10 years
But; n = time ÷ half life
= 40 years ÷ 10 years
= 4
Thus, the number of half lives in 40 years is 4.
