Moles = mass / Mr
= 0.4243 / 100.1
= 4.239 x 10⁻³ mole of CaCO₃
Answer:
2.5L [NaCl] concentrate needs to be 4.8 Molar solution before dilution to prep 10L of 1.2M KNO₃ solution.
Explanation:
Generally, moles of solute in solution before dilution must equal moles of solute after dilution.
By definition Molarity = moles solute/volume of solution in Liters
=> moles solute = Molarity x Volume (L)
Apply moles before dilution = moles after dilution ...
=> (Molarity X Volume)before dilution = (Molarity X Volume)after dilution
=> (M)(2.5L)before = (1.2M)(10.0L)after
=> Molarity of 2.5L concentrate = (1.2M)(10.0L)/(2.5L) = 4.8 Molar concentrate
The one with the highest pH would be a solution with 100 mL of water and also 20 mL of 0.1 M NaOH is added. Solutions without buffers would have the highest pH since the resistance to change is very low. Hope this answers the question.
When you mix pure water and salt(sodium chloride) you will make a saline solution.
Saline solution with 0.9% concentration is used frequently in the medical field for resuscitation fluid because it will have same molarity with the body fluid, so it won't induce fluid exchange caused by osmosis.