Question #1
Potasium hydroxide (known)
volume used is 25 ml
Molarity (concentration) = 0.150 M
Moles of KOH used
0.150 × 25/1000 = 0.00375 moles
Sulfuric acid (H2SO4)
volume used = 15.0 ml
unknown concentration
The equation for the reaction is
2KOH (aq)+ H2SO4(aq) = K2SO4(aq) + 2H2O(l)
Thus, the Mole ratio of KOH to H2SO4 is 2:1
Therefore, moles of H2SO4 used will be;
0.00375 × 1/2 = 0.001875 moles
Acid (sulfuric acid) concentration
0.001875 moles × 1000/15
= 0.125 M
Question #2
Hydrogen bromide (acid)
Volume used = 30 ml
Concentration is 0.250 M
Moles of HBr used;
0.25 × 30/1000
= 0.0075 moles
Sodium Hydroxide (base)
Volume used 20 ml
Concentration (unknown)
The equation for the reaction is
NaOH + HBr = NaBr + H2O
The mole ratio of NaOH : HBr is 1 : 1
Therefore, moles of NaOH used;
= 0.0075 moles
NaOH concentration will be
= 0.0075 moles × 1000/20
= 0.375 M
Here we go ~
Energy difference btween the two electronic states can be expressed as :
[ h = planks constant,
= frequency ]
Answer:
carbon dioxide is acidic and when it comes in contact with blue litmus paper it turns red
Explanation:
Answer:
Explanation: because more is always better
Answer:
7.69x
Explanation:
The ionization is the energy necessary to transform an atom in an anion. So, it's the energy it requires to gain an electron.
This ionization occurs for the photoelectric effect - the emission of electrons by metal using photons. So, if the efficiency is 100%, 1 photon can ionize 1 atom, but for an effficiency of 13.0%:
N = 
N = 7.69x
Where N is the number of photons.
