Yes. Whenever a chemical change is observed (a few examples being change in color, odor, or precipitate formation) a new substance is formed.
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 .
Answer: A.nitrogen,oxygen,and argon
Explanation:
Answer:
fluorine (F), and chlorine (Cl) because they are both halogens and belong to the same group in the periodic table
Explanation:
The pair of non - metals in the elements given that will have similar properties are chlorine and Fluorine.
This is because they both are elements commonly known by the group name Halogens which belong to group 7A.
Properties of halogens include;
- They are very reactive, have single covalent bonds and readily form other compounds.
- In the gaseous state, they will form diatomic covalent molecules.
Whereas, helium is a group 8 element, oxygen is a group 6 element while carbon is a group 4 element.
