Question 1
What happens to the pH of water when magnesium oxide is dissolved into it?
The pH increases, because MgO is acidic
The pH decreases, because MgO is basic
The pH increases, because MgO is basic
Nothing happens because MgO is neutral
What happens to the pH of water when magnesium oxide is dissolved into it?
The pH increases, because MgO is acidic
The pH decreases, because MgO is basic
The pH increases, because MgO is basic
Nothing happens because MgO is neutral
The Group II metals have higher melting points than the Group I metals.
Which factors result in Group II metals having higher melting points?
1 only
1 and 2 only
2 and 3 only
1, 2 and 3
What happens when iodine is bubbled through aqueous potassium bromide?
Iodine is oxidised to iodide ions
Potassium bromide is reduced to bromine
Bromide ions are oxidised to bromine
No reaction occurs
The halogens exist as diatomic molecules, X2.
Descending down Group 17 from chlorine to iodine the boiling points of the elements increase.
Which statement explains this trend?
The permanent dipole in the X2 molecule increases as the group is descended
The X–X bond strength increases as the group is descended
The electronegativity of X decreases as the group is descended
The number of electrons in each X2 molecule increases as the group is descended
How do the strengths of the forces between molecules, and the bonds within molecules, vary going down Group 17 from chlorine to bromine to iodine?
strength of London dispersion forces | strength of covalent bonds | |
A | increase | increase |
B | decrease | increase |
C | increase | decrease |
D | decrease | decrease |
Most non-metallic oxides can be described as
Ionic and alkaline
Covalent and alkaline
Covalent and acidic
Ionic and acidic
Which of the options below correctly contains a basic, acidic and amphoteric oxide?
K2O, SrO, Al2O3
BeO, Al2O3, Br2O
Al2O3, SiO2, P4O10
P4O10, SO3, F2O
Which pair of elements reacts most readily?
Li + Br2
Li + Cl2
K + Br2
K + Cl2
Chlorine is a greenish-yellow gas, bromine is a dark red liquid, and iodine is a dark grey solid.
Which property most directly causes these differences in volatility?
The halogen–halogen bond energy
The number of neutrons in the nucleus of the halogen atom
The number of outer electrons in the halogen atom
The number of electrons in the halogen molecule
Which property increases down group 1 from lithium to caesium?
Chemical reactivity
First ionisation energy
Melting point
Electronegativity