1.3 Bonding Flashcards
What is a compound?
Compounds are atoms of different elements chemically bonded together.
What is ionic bonding?
Ionic bonding is when ions are held together by electrostatic attraction.
(see page 24 in the revision guide for some more information)
What ions are formed in group 1?
1+ ions
What ions are formed in group 2?
2+ ions
What ions are formed in group 6?
2- ions
What ions are formed in group 7?
1- ions
What charge is a sulphate ion?
SO4 2-
What charge is a hydroxide ion?
OH-
What charge is a nitrate ion?
NO 3-
What charge is a carbonate ion?
CO3 2-
What charge is ammonium?
NH 4+
Describe the structure of sodium chloride.
(see page 25 in the revision guide)
How does ionic structure explain the behaviour of ionic compounds?
- Ionic compounds conduct electricity when they’re molten or dissolved.
- Ionic compounds have high melting points.
- Ionic compounds tend to dissolve in water.
(see page 25 in the revision guide for a detail of each)
What is a molecule?
A molecule is two or more atoms bonded together.
Molecules are help together by strong covalent bonds.
How do electrons relate to a covalent bond?
A single covalent bond contains one shared pair of electrons.
How does the structure of graphite explain its properties?
(see page 26 in the revision guide)
How does the structure of diamond explain its properties?
(see page 27 in the revision guide)
What is dative bonding?
Dative bonding is where both electrons come from one atom in a covalent bond.
(see page 27 in the revision guide for an example)
Draw the shape of a linear molecule, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of a trigonal planar model, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of a tetrahedral molecule, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of a trigonal pyramidal, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of a bent molecule, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of a trigonal bipyramidal molecule, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of a seesaw molecule, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of an octahedral molecule, what is its bond angle?
(see page 29 in the revision guide)
Draw the shape of a square planar molecule, what is its bond angle?
(see page 29 in the revision guide)
Predict the shape of the molecule H2S
(see page 29 in the revision guide)
What is electronegativity?
Electronegativity is the atoms ability to attract the electron pair in a covalent bond.
(see page 30 in the revision guide to see the electronegativity of some elements)
How are covalent bonds polarised?
(see page 30 in the revision guide)
Describe Van der Waals forces.
(see page 31 in the revision guide)
Describe hydrogen bonding.
(see page 32 in the revision guide)
What are the three types of intermolecular forces?
- Induced dipole-dipole or Van der Waals forces.
- Permanent dipole-dipole forces.
- Hydrogen bonding.
Draw and describe the structure of metals.
Metal elements exist as giant metallic lattice structures.
see page 33 in the revision guide for a diagram and description
How does metallic bonding explain the properties of metals?
(see page 33 in the revision guide)
Describe the physical properties of a solid, liquid and a gas.
(see page 33 in the revision guide)
What type of bonding is NaCl and MgCl2?
Ionic.
What type of bonding is CO2, I2 and H2O?
Simple covalent (molecular)
What type of bonding is diamond, graphite and SiO2?
Giant covalent (macromolecular)
What type of bonding is Fe, Mg and Al?
Metallic.
Do NaCl and MgCl2 have high or low melting points?
High.
Do CO2, I2 and H2O have high or low melting points?
Low, (involves breaking intermolecular forces but not covalent bonds)
Do diamond, graphite and SiO2 have high or low melting points?
High.
Do Fe, Mg and Al have high or low melting points?
High.
What is the state of NaCl and MgCl2 at room temperature?
Solid.
What is the state of CO2, I2 and H2O at room temperature?
May be solid (like I2) but usually liquid or gas.
What is the state of diamond, graphite and SiO2 at room temperature?
Solid.
What is the state of Fe, Mg and Al at room temperature?
Solid.
Do NaCl and MgCl2 conduct electricity?
No because the ions are held in place.
Do CO2, I2 and H2O conduct electricity?
No
Do diamond, graphite and SiO2 conduct electricity?
No (except graphite)
Do Fe, Mg and Al conduct electricity?
Yes (delocalised electrons)
Substance X has a melting point of 1045K. When solid, it is an insulator, but once melted it conducts electricity. Identify the type of structure present in substance X.
Ionic.
see page 35 in the revision guide
Draw the shape of BeCl2
(see page 29 in the revision guide)
Draw the shape of BF3
(see page 29 in the revision guide)
Draw the shape of NH4+
(see page 29 in the revision guide)
Draw the shape of PF3
(see page 29 in the revision guide)
Draw the shape of H2O
(see page 29 in the revision guide)
Draw the shape of PCl5
(see page 29 in the revision guide)
Draw the shape of SF4
(see page 29 in the revision guide)
Draw the shape of ClF3
(see page 29 in the revision guide)
Draw the shape of SF6
(see page 29 in the revision guide)
Draw the shape of XeF4
(see page 29 in the revision guide)
Give the definition of ionic bonding.
Ionic bonding is the electrostatic force of attrition between oppositely charged ions formed by electron transfer.
What ions do metal atoms form?
Metal atoms lose electrons to form +ve ions.
What ions do non-metal atoms form?
Non-metal atoms gain electrons to form -ve ions.
Is the melting point higher in smaller, higher charged ions or in larger, lower charged ions? Explain your answer.
Ionic bonding is stronger and the melting points higher when the ions are smaller and/or have higher charges.
Which has the higher melting point, NaCl or MgO?
MgO has a higher melting point than NaCl as the ions involved (Mg2+ and O2-) are smaller and have higher charges than those in NaCl (Na+ and Cl-)
Give the definition of a covalent bond.
A covalent bond is a shared pair of electrons.
Give the definition of a dative covalent bond / co-ordinate bonding.
A dative covalent bond forms when the shared pair of electrons in the covalent bond come from only one of the bonding atoms.
Draw the 3D structure of H3O+.
(see page 1 in the chemrevise revision guide)
Draw the 3D structure of NH4+
(see page 1 in the chemrevise revision guide)
Draw the 3D structure of NH3BCl3
(see page 1 in the chemrevise revision guide)