Answer:
Explanation:
Let A₀ = the original amount of ⁵⁵Co
.
The amount remaining after one half-life is ½A₀.
After two half-lives, the amount remaining is ½ ×½A₀ = (½)²A₀.
After three half-lives, the amount remaining is ½ ×(½)²A₀ = (½)³A₀.
The general formula for the amount remaining is:
A =A₀(½)ⁿ
where n is the number of half-lives
n = t/t_½
Data:
A = 1.90 ng
t = 45 h
t_½ = 18.0 h
Calculation:
(a) Calculate n
n = 45/18.0 = 2.5
(b) Calculate A
1.90 = A₀ × (½)^2.5
1.90 = A₀ × 0.178
A₀ = 1.90/0.178 = 10.7 ng
The original mass of ⁵⁵Co was .
Dependent is a variable who's outcome depends on another variable. independent is a variable who's outcome doesn't depend on another variable only the researchers experimenting.
hope this helps !
1/8 would remain...
(1/2 is 10 years
1/4 is 20 years
1/8 is 40 years)
Hope this helps! :)
Answer : chemical reaction
Mixing an acid with a base is a common chemical reaction.
Ba(ClO3)2 --> BaCl2 + 3 O2
The fact that there are some ionic compounds doesn't matter. Just use the formulas.
barium chlorate = Ba(ClO3)2
barium chloride = BaCl2
Oxygen = O2
Now create the unbalanced equation
Ba(ClO3)2 --> BaCl2 + O2
And balance in the usual fashion. Count the atoms of each element on both sides
Ba = 1, 1
Cl = 2, 2
O = 6, 2
And oxygen is out of balance. But can be easily handled with a 3 coefficient on the right hand side. So:
Ba(ClO3)2 --> BaCl2 + 3 O2
And we have a balanced equation.
