Answer:
The correct option is;
It is always necessary to include a Roman numeral after the symbol of the metal
Explanation:
The transition metals can form ionic compounds with other elements by giving different number of electrons such that the transition metals can combine to form compounds in which they have different oxidation states
Therefore, in a compound formed by a transition metal, the value of the transition metal's valency or oxidation state in the compound is indicated by the inclusion of an equivalent Roman numeral after the transition metal in the name of the chemical formula of the compound
A vestigial structure is a feature of an organism's body that was once an adaptation shaped by natural selection, but which is no longer useful in their current environment. For example, some species of fish that live in completely dark caves have eyes, although their eyes cannot see and serve no function.
<span>Acetone has a density of 784 kg/mÂł (this you can look up).
This equals 784.000 g/mÂł (kilo means 1000).
Which can be converted to 0.784 g/cm3 (1 m3 is 1.000.000 cm3).
A cm3 is exactly 1 ml. So 0.784 g/cm3 = 0.784 g/ml.
We have 6.68 gram of acetone. 6.68 g / 0.784 g/ml = 8.52 ml.
So the volume of 6.68 grams of acetone is 8.52 ml.</span>
Ka expression for any substance:
Ka = [H+] [A-] / [HA]
In this case,
Ka = [H+][C₃H₅O₃-]/[C₃H₆O₃]
1.4 x 10⁻⁴ = [H+] [C₃H₅O₃-] / [C₃H₆O₃]
pKa = -log(Ka)
pH = -log([H+])
The difference between pKa and pH is that pH is the negative logarithm of only the concentration of hydrogen ions, while pKa is the negative logarithm of the ratio of the product of the concentrations of hydrogen ions and concentration of base to the concentration of acid.