How many grams of KNO3 are needed to make 1.50 liters of a 0.50 M KNO3 solution?

Evaporation: this is when warmth from the sun causes water from oceans, lakes, streams, ice and soils to rise into the air and turn into water vapour (gas). water vapour droplets join together to make clouds! condensation: this is when water vapour in the air cools down and turns back into liquid water.

Vander waals forces are inter molecular bonds that exist within molecules of the same substance. a water molecule is made up of oxygen and hydrogen atoms which share electrons between each other. the vander waals forces are forces that exist between multitude of different  molecules of water. dipole dipole forces is the type of vander waals force that exist in water. the oxygen atom which is more electronegative pulls the shared electron closer to itself thus generating a partial negative charge while the hydrogen acquire a partial positive charge. these two different charges causes attraction to occur in water molecules.

Using dilution equationm1v1 =m2v2 ; where m1 and m1 are the intiial and final concentration, and v1 and v2 are the initial and final volume.5  × 5 m = 8 l  × m2m2 = 25/8 = 3.125 mtherefore; the resulting molarity is 3.125 m