The number of hours required : 37.2 hours
<h3>Further explanation</h3>
Given
⁴²K (potassium -42)
Required
The number of hours
Solution
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually, radioactive elements have an unstable atomic nucleus.
Based on Table N(attached), the half-life for ⁴²K is 12.4 hours, which means half of a sample of ⁴²K will decay in 12.4 hours
For three half-life periods :

Answer: The metalloids are a group of elements in the periodic table. They are located to the right of the post-transition metals and to the left of the non-metals. Metalloids have some properties in common with metals and some in common with non-metals.
Explanation:
Answer:
520ML and apparently I need to put more in this answer
Explanation:
brainly.com
The percentage composition of this compound : 40%Ca, 12%C and 48%O
<h3>Further explanation</h3>
Given
20.0 g of calcium,
6.0 g of carbon,
and 24.0 g of oxygen.
Required
The percentage composition
Solution
Total mass of compound :
=mass calcium + mass carbon + mass oxygen
=20 g + 6 g + 24 g
=50 g
Percentage composition :



Answer:
The answer to your question is 0.5 liters
Explanation:
Data
[CaCl₂] = 4.0 M
number of moles = 2
volume = ?
Process
To solve this problem use the formula of Molarity and solve it for volume, substitute the values and simplify.
-Formula
Molarity = moles / volume
-Solve for volume
Volume = moles / molarity
-Substitution
Volume = 2/4
-Simplification
Volume = 0.5 liters.