Answer:
2s2 2p5
Rb < Sr< Sn< Te<I
Explanation:
Electron affinity is the ability of an atom to accept electrons to form negative ions.
Electron affinity is a periodic trend that decreases down the group but increases across the period.
This accounts for the trends observed in the answer. The atom having the electronic configuration, 2s2 2p5 must be a halogen and it exhibits the highest value of electron affinity.
Also, since electron affinity increases across the period, the electron affinities of the elements increases. Therefore, the arrangement of atoms as shown in the answer depends on increasing electron affinity.
Lets name the unknown metal as M. Cation would be M³⁺.
the molecular formula of the compound is M₂(SO₄)₃
the mass of one mole - (molar mass of M x2 + 3 x molar mass of SO₄²⁻)
= 2M + 96 x 3
= 2M + 288
In 1 mol if there's 72.07% of sulphate ,
then 72.07 % corresponds to 288 g
1 % is then - 288/72.07
100 % of the compound - 288/72.07 x 100
molar mass of the compound - 399.6 g/mol
mass of 2M - 399.6 - 288 = 111.6 g
molar mass of M - 111.6 /2 = 55.8 g/mol
the element with molar mass of 55.8 is Fe.
Unknown metal is iron(III) , Fe³⁺
The answer to the question is b
I think the most appropriate answer is: the solvent being used in the experiment
<span>To correct for any light absorption not originating from the solute you will need to calibrate the tools with a solution that most similar to the sample.
Blank covete or standard solution can be used, but it was not ideal. By using the solvent as calibration, you can remove the reading from the solvent so your result only comes from the sample.
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