Flashcards in Bonding Deck (30)
Define an ionic bond
The electrostatic force of attraction between oppositely charged ions formed by electron transfer
Define covalent bond
A shared pair of electrons
Define a dative covalent bond
The shared pair of electrons in the covalent bond come from only one of the bonding atoms
Define a metallic bond
The electrostatic force of attraction between the positive metal ions and the delocalised electrons
What are the 3 factors which affect the strength of a metallic bond and state which ones lead to a stronger metallic bond?
Number of protons (more=stronger bond)
Number of delocalised electrons per atom (more=stronger bond)
Size of atom (smaller=stronger bond),
What are 4 examples of macromolecular covalent structures?
What’s the solubility like of ionic compounds in water?
What’s the solubility like of simple molecular compounds in water?
What’s the conductivity like of ionic compounds when solid, and why?
Poor as Ions can’t moved
What’s the conductivity like of ionic compounds when molten, and why?
Good as ions can move
What’s the name and bond angle of the shape with 4 bonding pairs and 0 lone pairs
Tetrahedral and 109.5°
What’s the name and bond angle of the shape with 3 bonding pairs and 1 lone pairs
Trigonal Pyramidal and 107°
What’s the name and bond angle of the shape with 2 bonding pairs and 2 lone pairs
Bent and 104.5°
What’s the name and bond angle of the shape with 5 bonding pairs and 0 lone pairs
Trigonal Bipyramidal and 120° and 90°
What’s the name and bond angle of the shape with 6 bonding pairs and 0 lone pairs
Octahedral and 90°
Relative tendency of an atom in a covalent bond in a molecule to attract electrons in a covalent bond to itself
What is the scale where electronegativity is measured in?
What factors affect electronegativity?
Number of protons
Distance from the nucleus (atomic radius)
What is the most electronegative element?
What value does the most electronegative element have on the electronegativity scale?
Why is CCl4 non-polar whilst CH3Cl polar?
CH3Cl is asymmetrical due to the presence of C-Cl bond which is polar
In polar covalent bonds what slight charge does carbon and hydrogen atoms tend to have?
What makes a compound purely covalent?
Small electronegative difference between elements
What makes a compound mostly ionic?
Large electronegative difference between elements
What is the relationship between symmetry and polarity
Symmetrical are non-polar
Which substances show van der waals forces?
Which substances do not show van der waals forces?
When do permanent dipole-dipole forces occur?
When there is a difference in electronegativity between elements/elements that are polar
When does hydrogen bonding occur and what must be present?
Between hydrogen and either fluorine, oxygen and nitrogen. There must be also be a lone-pair of electrons.