Ionic compounds
Transfer of electrons makes ionic compounds.
A compound of sodium
Sodium chloride, NaCl, is a compound of sodium and chlorine.
How is NaCl built?
What this lesson covers
The idea
Compounds formed by transfer of electrons from a metal to a non-metal are ionic (electrovalent) compounds; their oppositely charged ions are held by strong electrostatic forces and exist as aggregates of ions, not molecules.
A compound of sodium
Sodium chloride, NaCl, is a compound of sodium and chlorine.
How is NaCl built?
- Of oppositely charged ions held together
- Of single small molecules of NaCl
- Of neutral atoms only
Build sodium chloride
Press Next step.
Ionic bonding
When a metal gives electrons to a non-metal, ions form. Opposite charges attract strongly. The result is an ionic compound, also called an electrovalent compound. It is not made of molecules but of aggregates of ions.
Compounds formed by transfer of electrons from a metal to a non-metal are ionic (electrovalent) compounds; their oppositely charged ions are held by strong electrostatic forces and exist as aggregates of ions, not molecules.
Notes
Metal to non-metal electron transfer gives ionic (electrovalent) compounds: oppositely charged ions held by strong electrostatic forces in aggregates, not molecules.
Check yourself
Compounds formed by the transfer of electrons from a metal to a non-metal are called ...
Sodium chloride exists as ...
What holds the sodium and chloride ions together?
In magnesium chloride, each Mg²⁺ ion goes with how many Cl⁻ ions? (Each Cl⁻ has a charge of −1.)
Answer: 2
Charges must balance: +2 needs 2 × (−1) = −2, so 2 chloride ions.
- ionic or electrovalent compounds — correct. Yes!
- allotropes. Allotropes are different forms of one element, like diamond and graphite.
- alloys. Alloys are homogeneous mixtures of metals with other metals or non-metals.
- separate NaCl molecules. The book says sodium chloride does not exist as molecules.
- aggregates of oppositely charged ions — correct. Yes!
- a mixture of sodium and chlorine atoms. It is made of ions, Na⁺ and Cl⁻, not of neutral atoms.
- Their equal charges. Equal charges repel; sodium and chloride ions have opposite charges.
- Nothing at all; they just lie close. The oppositely charged ions attract each other strongly.
- Strong electrostatic forces of attraction — correct. Yes!