Answer:
0.625 g
Explanation:
Given data:
Half life of radon-222 = 3.8 days
Total mass of sample = 10 g
Mass left after 15.2 days = ?
Solution:
Number of half lives = T elapsed / Half life
Number of half lives = 15.2 / 3.8
Number of half lives = 4
At time zero = 10 g
At first half life = 10 g/2 = 5 g
At 2nd half life = 5 g/ 2= 2.5 g
At third half life = 2.5 g/2 = 1.25 g
At 4th half life = 1.25 g/2 = 0.625 g
Answer:
1. an object that has been intentionally placed into orbit. they are called Artificial Satalites.Satanists.
2. a huge collection of gas ,dust and billions of stars and their solar systems held together by gravity.
3. a large object such as Jupiter or Earth that orbits a star. planets are smaller than stars and they do not produce light.
4. July 16, 1969
Answer:
There are 40 electrons in one atom of Zirconium.
Explanation:
Note: The word is not zicronium, it is Zirconium.
Iconic +covalent is the answer to this
Answer:I think it’s A.Positive. Not sure though.
Explanation: