Module 2: Chapter 5.5 - Bonding and structure Flashcards
(20 cards)
What is ionic bonding
loss of electrons by metal atoms form a positively charged ion and gain of electrons from a non metal form a negatively cahrged ion
What is a ionic bond
The electrostattic attractions between oppositly charged ions
Cations are formed when…
… atoms lose electroms to non metals
Anions are formed when…
…atoms gain electrons from metals
ions are (……….) with the nearest noble gas
isoelectronic
Explain the structure of a giant ionic lattice
The oppositely charged ions in a giant ionic lattice are held together by strong ionic bonds which are strong electrostatic forces of attraction acting in all directions
Explain in terms of structure why giant ionic lattices have high melting and boiling points
Giant ionic lattices are regular structures, held together by ionic bonds. (1) these ionic bonds are strong electrostatic forces of attraction between oppositely charged ions, acting in all directions.(1) it takes a lot of energy to break these strong electrostatic forces of attraction between the oppositely charged ions (1) As a result, an ionic compound will have a high melting or boiling point.
Why can’t ionic compounds conduct electricity in a solid state
ionic compounds can only conduct electricity when molten or dissolved because only then are the ions of the compound able to move and carry charge. Ionic compounds are unable to conduct electricity when solid because the ions are fixed in place and unable to carry charge.
Why are ionic compounds highly soluble
Ionic compounds easily dissolve in water which means they are highly soluble in water. This is because both ionic compounds and water molecules are partially charged molecules (polar). This means the partial charges of water break apart the ionic lattice, pulling oppositely charged ions apart and the ionic compound to dissolve.
What is a covalent bond
A covalent bond is the strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms
What is the difference between Ionic Bonding and Covalent Bonding?
Ionic bonding involves the transfer of electrons between atoms, whereas covalent bonding involves the sharing of electrons between atoms. Ionic bonding results in the formation of positive and negative ions, while covalent bonding results in the sharing of electrons between atoms.
What are some common examples of Ionic Compounds?
sodium chloride (NaCl),
magnesium oxide (MgO),
calcium chloride (CaCl2).
What are the properties of covalent structures?
- They are generally stable and do not easily break apart
- They are typically solids with low melting and boiling points
- They are poor conductors of electricity
- They are typically non-polar, meaning they do not have a positive or negative charge.
How do covalent bonds affect the reactivity of a substance?
Covalent bonds affect the reactivity of a substance because they hold the atoms together in a strong bond. This means that the substance is typically less reactive than substances with weaker bonds, as it requires more energy to break the covalent bonds and initiate a reaction.
Why do simple covalent bonds have a low melting point
the simple molecules that make up the compound are arranged in a regular lattice held together by weak intermolecular forces. As these interactions are very weak, not much energy is required to overcome them, which results in simple molecular structures usually being gaseous or liquid at room temperature.
Why can’t covalent compounds conduct electricity
because there are no mobile ions or electrons to carry the current.
Why do giant covalent structures have high melting/boiling points
A giant covalent structure involves lots of covalent bonds present between several atoms which forms a giant lattice. The large number of strong covalent bonds involved means that large amount of energy is required to break them apart.
What is single covalent bonding
A single covalent bond contains a shared pair of electrons. Each covalent bond involves two electrons which makes up the shared pair of electrons. Each electron from the electron pair comes from each of the atoms involved in the covalent bond.
What is multiple covalent bonding
A multiple covalent bond can be either a double or triple covalent bond and it is when atoms share several pairs of electrons rather than just a single pair.
Double - when atoms share two pairs of electrons.
Triple - when atoms share three pairs of electrons
What is dative covalent bonding
A dative covalent bond contains a shared pair of electrons donated by one atom only. In a dative covalent bond both electrons in the electron pair come from one atom in the bond.
