All alcohols are polar.
True
Answer:
Weak acid
Explanation:
A titration curve is a graphical description of the change in pH of the solution in the conical flask as the reagent is added from the burette. A titration curve can be plotted for the different kinds of acid and base titrations. The volume of the titrant is always plotted as the independent variable and the pH of the solution as the dependent variable. The equivalence point is read off from the titration curve. A titration curve is very important because it shows the pH at various points during the titration.
A weak acid/strong base titration leads to an equivalence point above 7. From the question, we were told that the pH at equivalence point lies around 8. Hence the unknown substance must be a weak acid.
Answer:
0.0876L of 0.478M Na₃PO₄ are needed
Explanation:
The reaction of calcium chloride, CaCl₂, with sodium phosphate, Na₃PO₄ is:
3CaCl₂ + 2Na₃PO₄ → Ca₃(PO₄)₂ + 6NaCl
<em>Where 3 moles of calcium chloride react with 2 moles of sodium phosphate to produce 1 mole of calcium phosphate.</em>
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To solve this question we need to find moles of CaCl₂ added. Using the reaction we can find the moles of Na₃PO₄ that are needed to react completely and the volume using its concentration:
<em>Moles CaCl₂:</em>
0.225L * (0.279mol / L) = 0.0628moles of CaCl₂
<em>Moles Na₃PO₄:</em>
0.0628moles of CaCl₂ * (2mol Na₃PO₄ / 3 mol CaCl₂) =
0.0419moles of Na₃PO₄
<em>Volume 0.478M Na₃PO₄:</em>
0.0419moles of Na₃PO₄ * (1L / 0.478mol) =
<h3>0.0876L of 0.478M Na₃PO₄ are needed</h3>
Because you always take the second number from the group number and it gives you the charge amount.