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
Answer:
Two Half-lives
Explanation:
Let number of Parent nuclei Initially present be X,
Then, finally
Parent nuclei Will remain with
daughter nuclei.
In one half- life , parent nuclei becomes half of initial.
So, starting with X parent nuclei,
After one half-life, it will degrade to
.
After another half life , Parent nuclei will become half of
Which is equal to
.
So, Parent nuclei have to go through Two half-lives.
Answer:


Explanation:
Hello,
Considering the given reaction's stoichiometry, grams of oxygen result:

Moreover, the mass of produced carbon dioxide turns out:

Best regards.
Diphosphorus tetraiodide is a covalent compound.
It has low melting point as compared to ionic compounds
It is a rare compound where the oxidation state of Phosphorous is +2.
It is also termed as subhalide of phosphorous.
Answer:
Yes it is
Explanation: because it is composed of identical molecules consisting of atoms of two or more chemical elements.
hope it helps <3