Answer: Chromium is less reactive as compared to Aluminium as it can not easily electrons as aluminium.
Explanation:
The arrangement of metals in a series according to the decreasing order of their reactivity is called reactivity series.
The metals that are placed above hydrogen are more reactive and those below hydrogen are less reactive.
A metal placed above another metal can displace lower metal from its salt solution. Thus a metal placed above in series is more reactive than metals placed below it.
As aluminium can easily lose electrons as compared to chromium , it is more reactive than Chromium.
Answer:
<u> </u><u>85.952 ml</u> needed to titrate the excess complexing reagent .
Explanation:
Lets calculate
After addition of 80 ml of EDTA the solution becomes = 20 + 70 = 90 ml
As the number of moles of =
=
=0.01172
Molarity =
=
=0.000586 moles
Excess of EDTA = concentration of EDTA - concentration of CoSO4
= 0.009005 - 0.000586
= 0.008419 M
As M1V1 ( Excess of EDTA ) = M2V2
V2 =85.952 ml
Therefore , <u>85.952 ml </u> needed to titrate the excess complexing reagent .
Answer:
Explanation:
Sodium and potassium are present in group 1A. Both are alkali metals.
The atomic number of sodium is 11 and potassium is 19. Sodium is present in period 3rd while potassium is present in period 4th.
Electronic configuration of sodium:
Na₁₁ = 1s² 2s² 2p⁶ 3s¹
K₁₉ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
It can be seen in electronic configuration that in case of sodium the valance electron is present in third energy level while in case of K outer most electron is present in 4th energy level. So atomic structure of sodium has three energy level and K has four energy level that's why radius of potassium is greater than sodium because its the distance from center to outer most electronic shell.
Moreover as we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
OPTION D IS YOUR ANSWER.............