<p>Can someone explain to me how you arrive at the answer for question 16 on the science section of the fourth ACT practice test in the real book? It's the CaCl2 and NaCl moles question.</p>
<p>When CaCl2 dissolves, it breaks up into the three component atoms: 1 calcium and 2 chlorines. When NaCl dissolves, it breaks up into the two component atoms: 1 sodium and 1 chloride. Thus, when 0.1 moles of CaCl2 dissolves, it breaks up into 0.3 moles of particles (0.1 moles of molecules times 3 particles per mole of molecules). If CaCl2 has the same effect PER PARTICLE as NaCl, then you it would have the same effect as 0.15 moles of NaCl because 0.15 moles of NaCl contains 0.30 moles of particles (2 particles per mole). Thus the value will be between 0.1 and 0.2 moles of NaCl in the table.</p>
<p>Alright thanks for the explanation. I couldn’t understand the Red Book’s explanation at all… @viserion</p>