The HCl added = 1.25 moles
and the moles of Na2HPO4 = 1 mole
Now when acid is added in the given solution of Na2HPO4
One mole of H+ will react with one mole of Na2HPO4 to given one mole of NaH2PO4
Na2HPO4 + H+ ---> NaH2PO4
Now this one mole formed NaH2PO4 will further react with 0.25 moles of H+ left to form 0.25 moles of H3PO4 and 0.75 moles of NaH2PO4 will remain in the solution
So this will result into formation of a buffer of phosphoric acid and NaH2PO4
NaH2PO4 + H+ ---> H3PO4
pKa of H3PO4 = 2.1
so pH = pKa + log [salt] / [acid] = 2.1 + log [0.75 / 0.25] = 2.58
so the pH will be in between 2.1 to 7.2
The heat energy breaks down the bonds between the molecules of the solid so the molecules become looser. Further hearing of the liquid causes the bonds to be broken down and the molecules will move further apart.
At first sight it doesn't bode well. The key is in how firmly the protons and neutrons are held together. In the event that an atomic response produces cores that are more firmly bound than the firsts then vitality will be created, if not you should place vitality into make the response happen.
Answer: the correct option is A (A zero net force causes no change to an object's
motion.)
Explanation:
Force is a vector quantity that causes an object to accelerate or change velocity when pushed or pulled. While a NET FORCE can be defined as the combination of all forces acting on an object which is equally capable of accelerating the object.
When a NET FORCE is equal to zero( that is zero net force),there will be no change to an object's motion. When the net force of an object is equal to zero , it shows the object is in either static equilibrium( the objects velocity is zero) or dynamic equilibrium(where the object is moving at constant velocity). In both cases, the object remains motionless because the net forces is equal to zero.