Something moving. Change in temperature.
Answer:
C. 17 grams.
Explanation:
∵ mass % = [mass of solute/mass of solution] x 100.
mass of solute (NaCl) = ??? g & mass of solution = 140.0 g.
<em>∴ mass of NaCl = (mass %)(mass of solution)/100 </em>= (12.0)(140.0)/100 = <em>16.80 g ≅ 17.0 g.</em>
Answer:
a. Phosphoric Acid
b. Acetic Acid
c. Hypochlorous Acid
Explanation:
A buffer works when the pH of this one is in pKa ± 1. That means, to find which buffer system works in some pH you need to find pKa:
pKa = -log Ka
<em>pKa Acetic acid:</em>
-log1.8x10⁻⁵ = 4.74
<em>pKa phosphoric acid:</em>
-log7.5x10⁻³ = 2.12
<em>pKa hypochlorous acid:</em>
-log3.5x10⁻⁸ = 7.46
a. For a pH of 2.8 the best choice is phophoric acid because its effective range is: 1.12 - 3.12 and 2.8 is between these values.
b. pH 4.5. Acetic acid. effective between pH's 3.74 - 5.74
c. pH 7.5. Hypochlorous acid that works between 6.46 and 8.46
Solar flares form when prominences connect I think