the answer is probably A. improper orientation of molecules
C. Warm ocean currents bring warmer temperatures to coastal cities
First off, you must realize that the phase changes are marked by the points B and D on the graph. They are level because all of the energy (or heat) being added is being consumed by the physical process. So The temperature is increasing before the phase change, and after the phase change. The moments before and after are represented by points A, C, and E.
Answer:
HI (aq) → H⁺ (aq) + I⁻ (aq)
HI (aq) + H₂O(l) → H₃O⁺ (aq) + I⁻ (aq)
Explanation:
The Arrhenius acid concept indicates that a substance behaves like acid if it produces hydrogen ions H⁺ or hydronium ions H₃O⁺ in water. A substance will be classified as a base if it produces OH⁻ hydroxide ions in water. This way of defining acids and bases works well for aqueous solutions.
When we mix HI (aq) and water, we are increasing [H₃O⁺]
HI (aq) → H⁺ (aq) + I⁻ (aq)
HI (aq) + H₂O(l) → H₃O⁺ (aq) + I⁻ (aq)
A 0.250 L solution of NH4Cl contains (0.250 L)(0.35 mol/L) = 0.0875 moles of dissolved NH4Cl. Converting this quantity to mass, we get (0.0875 mol NH4Cl)(53.491 g/mol) = 4.7 g NH4Cl (two significant figures).
So, approximately 4.7 g of NH4Cl dissolved in a 0.250 L solution will have a concentration of 0.35 L.
