It is an open series circuit and this is why:
its obvious its a series circuit because all the symbols are in a straight rectangle.
its an open circuit because an open circuit has something that doesn't allow the electrons to flow all the way. and the thing blocking the electrons it the switch which is open, (off).
Hope this helped!! sorry its late!!
Answer:
The pH of the final solution is 7.15
Explanation:
50 mL of 2.0 M of 
and 25 mL of 2.0 M of 
were mixed to make a solution
Final volume of the solution after dilution = 200 mL
Final concentration of ![K_2HPO_4, [K_2HPO_4] = \frac{50 mL\times 2 M}{200 mL} = 0.5 M](https://tex.z-dn.net/?f=K_2HPO_4%2C%20%5BK_2HPO_4%5D%20%3D%20%5Cfrac%7B50%20mL%5Ctimes%202%20M%7D%7B200%20mL%7D%20%3D%200.5%20M)
Final concentration of![KH_2PO_4, [KH_2PO_4] = \frac{25 mL\times 2 M}{200 mL} = 0.25 M](https://tex.z-dn.net/?f=KH_2PO_4%2C%20%5BKH_2PO_4%5D%20%3D%20%5Cfrac%7B25%20mL%5Ctimes%202%20M%7D%7B200%20mL%7D%20%3D%200.25%20M)
We use Hasselbach- Henderson equation:
![pH = pK_a+ log \frac{[salt]}{[acid]}pka of KH_2PO_4 = 6.85](https://tex.z-dn.net/?f=pH%20%3D%20pK_a%2B%20log%20%5Cfrac%7B%5Bsalt%5D%7D%7B%5Bacid%5D%7Dpka%20of%20KH_2PO_4%20%3D%206.85)
Substituting the values:
Therfore, the pH of the final solution is 7.15
Your instructor is probably expecting the answer B) III only.
III) The evolution or <em>absorption of heat</em> is evidence of a <em>chemical change</em>.
I) Boiling water and IV) mixing paint are <em>physical changes</em>.
II) A change in colour on mixing is usually an indication of a reaction (but not when mixing paint). However, in this case, the lighter blue colour might have happened simply because you are diluting the solution. You would have to do an experiment which is correct.
Answer:
kindly refer to the picture attached
Explanation:
Have a great day . keep smiling
