Allred Rochow's Electronegativity of Element Calculator

Allred-Rochow's Electronegativity Formula:

\[ X_{A.R} = \frac{0.359 \times Z}{r_{covalent}^2} \]

Allred-Rochow's Electronegativity:

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1. What is Allred-Rochow's Electronegativity?

Definition: Allred-Rochow's electronegativity is a measure of the power of an atom in a molecule to attract electrons to itself.

Purpose: It helps predict the nature of chemical bonds and reactivity of elements in compounds.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ X_{A.R} = \frac{0.359 \times Z}{r_{covalent}^2} \]

Where:

\( X_{A.R} \) — Allred-Rochow's Electronegativity
\( Z \) — Effective Nuclear Charge
\( r_{covalent} \) — Covalent Radius (in Ångströms)

Explanation: The formula relates electronegativity to the effective nuclear charge experienced by valence electrons and the covalent radius of the atom.

3. Importance of Electronegativity Calculation

Details: Electronegativity values help predict bond polarity, molecular dipole moments, and chemical reactivity trends in the periodic table.

4. Using the Calculator

Tips: Enter the effective nuclear charge and covalent radius (in Ångströms). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is effective nuclear charge?
A: The net positive charge experienced by an electron in an atom, accounting for shielding by inner electrons.

Q2: How is covalent radius measured?
A: It's half the distance between two identical atoms bonded by a single covalent bond.

Q3: What's the range of Allred-Rochow electronegativity values?
A: Typically ranges from about 0.7 for cesium to 3.5 for fluorine.

Q4: How does this scale compare to Pauling's scale?
A: Both scales show similar trends, but numerical values differ. Pauling's scale is more commonly used.

Q5: Why is the constant 0.359 used?
A: This empirical constant scales the relationship to match observed electronegativity trends.