Answer:
atomic number- 42
chemical number- 96
number of protons-18
atomic mass-96
number of eletrons-42
number of valence eletrons- 1, 2, 13, or 18. (sorry i forgot)
nummber of shells in n=3 shell-18
number of neutrons-54
Explanation:
well i just know the periodic table by heart and thats how i got the answer XD
Answer:
25% thorium will left after 50 days.
Explanation:
Half life:
A nuclear half is the time period of radioactive material in which its amount remain halved.
In given question it is stated that the half life thorium-234 is 25 days. Which means after passing the 25 days the amount of thorium must be halved of original amount.
For example,
If the original concentration was 100%, than after 25 days it will be 50%.
After 50 days amount of thorium left:
Number of half life = T (elapsed) / T half life
Number of half life = 50/25
Number of half life = 2
At first half life amount of thorium left = 100/2 = 50
After second half life amount of thorium left = 50/2 = 25
Total amount decayed = 50+25 = 75
Amount left after 50 days = 100-75 = 25
25% thorium will left after 50 days.
Explanation: energy levels are three(counting number of cyecles) outer electrons are 3 also
Answer:3,3
I would say none because thats the only one that makes any sence.
The answer to your question is Coefficients.
*Hope this helps you! Feel free to message me if you have any further questions. Have a nice day! :)*