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:
Oxygen is the most abundant element in the Earth's crust.
Explaination: It makes up 46% of the mass of the Earths crust.
Answer:
Potential Energy is stored energy or energy of position (gravitational). The object isn't moving. For example, a ball being held is potential energy because the object isn't moving but it has the potential of turning into kinetic energy.
Kinetic Energy is the energy of motion. For example, running. You are moving, and there is clear action and activity
your answer is 0.00833M the volume was converted into liters
NaOH(aq)+HCl(aq)→NaCl(aq)+H2O(l)
Using the molarity equation, we can find the number of moles of HCl that reacted:
molarity=mol soluteL soln
mol solute=(molarity)(L soln)
mol HCl=(0.105molL)(0.0250L)=0.00263 mol HCl
(volume converted to liters)
Now, using the coefficients of the chemical reaction, we can determine the number of moles of NaOH that reacted:
0.00263mol HCl(1lmol NaOH1mol HCl)=0.00263 mol NaOH
Lastly, we'll use the molarity equation (using given volume of NaOH soln) again to determine the molarity of the sodium hydroxide solution:
molarity=mol soluteL soln
Answer:
sulfuric acid
Explanation:
When a battery is being discharged, the sulfuric acid in the electrolyte is being depleted so that the electrolyte more closely resembles water.