Final answer:
A chemist developing a new acid for etching metals should prioritize the chemical reactivity, focusing on properties like ionization energy and electron affinity. The acid's strength, reflected by its acid ionization constant (Ka), is also critical. Safety and economic viability are additional important considerations for the new acid.
Step-by-step explanation:
In developing a new acid to etch metals, a chemist should prioritize the chemical reactivity of the acid. This involves understanding and manipulating properties such as ionization energies (IE), electron affinities (EA), and the effective nuclear charge. Chemicals like hydrofluoric acid and ammonium bifluoride used in etching processes demonstrate the importance of these properties. A new acid should thus be developed with an appropriate balance between acidity and etching properties to effectively etch metal without causing unnecessary damage or posing excessive risk to the user.
The chemical property of the acid, in terms of its ability to donate protons to metals, is crucial. Its acid ionization constant (Ka) is a significant factor; a higher Ka value indicates a stronger acid, which could translate to more efficient etching. The chemist must also consider the safety and economic aspects of producing and using the new acid for etching metals.