Molarity is a unit of concentration defined as the number of moles of solute (the substance being dissolved) per volume of solution (the solvent in which all the solute is dissolved). Mathematically, molarity is expressed as
.
In this question, we are given the molarity and the volume of a solution of NaCl. We can use this information to calculate the number of moles of NaCl present in the solution. Rearranging the equation to solve for moles of solute, we multiply the molarity by the volume of the solution (the units for volume must be in liters, so 125 mL is expressed as the equivalent 0.125 L):

The question asks for the number of moles of NaCl in this solution, so number 3 would be correct.
Answer:
A solution was NOT formed.
Explanation:
For a solution to be formed, the green powder would need to dissolve in the water to form a homogenous mixture. But since the water was cloudy and had lumps of the green powder, it means that the powder did not dissolve, but instead remained insoluble.
The black swirly one, on the bottom right, is black hole. The one with rays coming out of it, the one next to the black hole, is super nova. Thats all I know im srry...
Answer:
The neutron is 30
Explanation:
The element with atomic number of 25 is Manganese. it has a mass number of approximately 55.
Therefore, the neutron number = Mass number - Proton number (i.e. atomic number)
= 55 - 25
Neutron number = 30