1. c. 35
2. <span>d. 1.26 x 10^24 molecules
3. </span><span>d. 303.6 g</span>
Answer:
D
Explanation:
because they need it and hii
Answer:
The exception in the order of the periodic table is;
B.) Cobalt is located before Nickel even though it has a higher average atomic mass
Explanation:
The Russian chemist Dmitri Mendeleev who formulated the periodic law, observed that the arrangement of the atoms in an order of their increasing atomic mass resulted in a table that show a recurring pattern in the properties of the elements within each group
However, cobalt (atomic mass 58.93 amu) which was heavier than nickel (atomic mass 58.71) was placed before nickel due to the similarities of its chemical properties to the group in which it was placed
It was later observed that cobalt with 27 protons was rightly placed to come before nickel that has 28 protons in the periodic table classified by atomic numbers which is the proton number.
Answer:
Concentration of hydroxide-ion at equivalence point =
Explanation:
1 mol of reacts with 1 mol of KOH to produce 1 mol of
At equivalence point, all gets converted to .
Moles of produced at equivalence point is equal to moles of KOH added to reach equivalence point.
So, moles of produced =
Total volume of solution at equivalence point = (25.00+43.76) mL = 68.76 mL
Concentration of at equivalence point =
produced at equivalence point is due to hydrolysis of . We have to construct an ICE table to calculate concentration of at equivalence point.
I:0.0897 0 0
C: -x +x +x
E: 0.0897-x x x
species inside third bracket represent equilibrium concentrations
So,
or,
So, M =
So, concentration of hydroxide-ion at equivalence point = x M =