8. Transition metals
9. Halogens
10. Nobel gasses
11. Lanthanides
12. Actinides
13. The tendency of a substance to undergo chemical reaction, either by itself or with other materials, and to release energy.
D is the answer.
On the left, there are 3 atoms of Ca, 2 atoms of Cr, 6 atoms of N, and 18 atoms of O.
On the right, there are 3 atoms of Ca, 9 atoms of N, 27 atoms of O, and 2 atoms of Cr.
Phenolphthalein is not a good indicator to use for a titration for a solution that has a ph of 6.0 at the equivalence point because the color change of the solution at this pH level is not sharp. It changes the color of the solution to pink starting from pH 8.3 to 10. A pH level lower than 8.3 would only show a colorless solution. Thus, you would not be able to distinguish whether the solution has reached its equivalence point at pH 6.0. It is best to use this indicator for a system that is using a strong base titrated with a weak acid.
The true statements are;
<h3>What is a redox reaction?</h3>
We define a redox reaction as one in which a specie is oxidized and another is reduced.
Now;
Eo cell = cell potential = -0.13 V - (+0.34 V) = -0.47 V
n =number of moles of electrons = 2 mole of electrons
K = equilibrium constant
ΔG = change in free energy
Eo cell = 0.0592/n log K
-0.47 = 0.0592/2 log K
log K = -0.47 * 2/0.0592
K = 1.3 * 10^-16
ΔG = -nFEo cell
ΔG = -(2 * 96500 * -0.47)
ΔG = 90.7kJ
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