Answer:
Considering the half-life of 10,000 years, after 20,000 years we will have a fourth of the remaining amount.
Explanation:
The half-time is the time a radioisotope takes to decay and lose half of its mass. Therefore, we can make the following scheme to know the amount remaining after a period of time:
Time_________________ Amount
t=0_____________________x
t=10,000 years____________x/2
t=20,000 years___________x/4
During the first 10,000 years the radioisotope lost half of its mass. After 10,000 years more (which means 2 half-lives), the remaining amount also lost half of its mass. Therefore, after 20,000 years, the we will have a fourth of the initial amount.
19. The atomic number is the same as protons and electrons unless it have a - or a + charge the electrons are going to change
%yield = 54.6%
<h3>Further explanation</h3>
Percent yield is the compare of the amount of product obtained from a reaction with the amount you calculated
(theoretical)
General formula:
Percent yield = (Actual yield / theoretical yield )x 100%
<h3 />
Reaction
2ZnS+3O₂ ⇒ 2ZnO+2SO₂
MW ZnS = 97.474 g/mol

MW ZnO = 81.38 g/mol
- mol ZnO (from mol ZnS as limiting reactant, O₂ excess)


Theoretical production = 125.388

Answer:
Strong acids. hope this helps :)