Answer : The radii of the two ions Cl⁻ ion and Na⁺ ion is, 181 and 102 pm respectively.
Explanation :
As we are given that the Na⁺ radius is 56.4% of the Cl⁻ radius.
Let us assume that the radius of Cl⁻ be, (x) pm
So, the radius of Na⁺ = 
In the crystal structure of NaCl, 2 Cl⁻ ions present at the corner and 1 Na⁺ ion present at the edge of lattice.
Thus, the edge length is equal to the sum of 2 radius of Cl⁻ ion and 2 radius of Na⁺ ion.
Given:
Distance between Na⁺ nuclei = 566 pm
Thus, the relation will be:
The radius of Cl⁻ ion = (x) pm = 181 pm
The radius of Na⁺ ion = (0.564x) pm = (0.564 × 181) pm =102.084 pm ≈ 102 pm
Thus, the radii of the two ions Cl⁻ ion and Na⁺ ion is, 181 and 102 pm respectively.
<u>Answer:</u> The mass of chlorine needed by the plant per day is 
<u>Explanation:</u>
We are given:
Volume o water treated per day = 25,000,000 gallons
Converting this volume from gallons to liters, we use the conversion factor:
1 gallon = 3.785 L
So, 
Amount of chlorine applied for disinfection = 10 mg/L
Applying unitary method:
For 1 L of water, the amount of chlorine applied is 10 mg
So, for 
of water, the amount of chlorine applied will be 
Hence, the mass of chlorine needed by the plant per day is
The arrangement of the elements in order of decreasing metallic character is: Rb, Zn, P, S, F, Ca, Co, Cr
<h3 /><h3>What are metals?</h3>
Metals are elements which are known by their special ability to form ions by a loss of electrons.
The increasing metallic character of metal is a measure of their ability to lose electrons.
Metallic character increases from right to left and down a group in the period table.
Metals are found to the left of the period table.
In conclusion, metals are known by their ability to lose electrons.
Learn more about metals at: brainly.com/question/25597694
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Three elements that are likely to have similar chemical and physical properties are
