M = n / V
Where, M is molarity (M or mol/L), n is number of moles of the solute (mol) and V is volume of the solution (L).
Here the solute is KNO₃.
The given molarity is 1.3 M
This means 1L of solution has 1.3 moles of KNO₃.
Hence moles in 600 mL = 1.3 M x 0.6 L = 0.78 mol
Therefore to make 1.3 M KNO₃ solution, needed moles of KNO₃ is 0.78 mol
Atomic models were developed through indirect observation even though no one had seen an atom. There were many experiments of which I know nothing about, but in the end the scientists managed to come up with a formula and various models to describe atoms.
Answer:
D
Explanation:
Oxygen is the 8th element in the periodic table. This means that oxygen has 8 protons and 8 electrons. In order to get the number of neutrons you take the atomic weight in this case 15.9999~16 and you subtract it by the number of protons (16-8).
The complete balanced chemical equation for this is:
<span>3KOH + H3PO4
--> K3PO4 + 3H2O</span>
First we calculate the number of moles of H3PO4:
moles H3PO4 = 0.650 moles / L * 0.024 L = 0.0156 mol
From stoichiometry, 3 moles of KOH is required for every
mole of H3PO4, therefore:
moles KOH = 0.0156 mol H3PO4 * (3 moles KOH / 1 mole
H3PO4) = 0.0468 mol
Calculating for volume given molarity of 0.350 M KOH:
Volume = 0.0468 mol / (0.350 mol / L) = 0.1337 L = 133.7
mL
Answer:
<span>133.7 mL KOH</span>
