Answer:
Approximately 
.
Explanation:
<h3>Number of moles of formula units of magnesium sulfate required to make the solution</h3>
The unit of concentration in this question is "
". That's equivalent to "
" (moles per liter.) In other words:
.
However, the unit of the volume of this solution is in milliliters. Convert that unit to liters:
.
Calculate the number of moles of 
formula units required to make this solution:
.
<h3>Mass of magnesium sulfate in the solution</h3>
Look up the relative atomic mass data of 
, 
, and 
on a modern periodic table:
Calculate the formula mass of using these values:
.
Using this formula mass, calculate the mass of that (approximately) 
of formula units:
.
Therefore, the mass of required to make this solution would be approximately .
The rate of evaporation is equal to rate of condensation in equilibrium......It means the evaporation rate becomes constant.....And thus equilibrium attained !!!
Destructive interference in which waves cancel each other out is depicted in region X,Y and Z.
<u>Explanation:</u>
Interface is the particle property of light waves. When incident light beam is made to pass through holes, the waves will combine either constructively or destructively. Constructive interference means the waves having same phase will get added so they will increase in amplitude. While destructive interference means the waves combining have different phases like crests and troughs. So they undergo decrease or complete vanishing of amplitude.
When waves combine in constructive interference, they form bright white light and when they combine in destructive interference, they form dark black light. So the regions X, Y and Z are shown as dark black colors in the diagram, so these regions represent destructive interference in which waves cancel each other out.
B, you can see there are 2 F atoms on each side of the equation
.
.
.
