It's Synthesis, single replacement is incorrect.
In ionic bonding, atoms SHARE ELECTRONS
Phase change is the solute
the one that doesn't phase change is the solvent.
A
To determine strength of attractive forces between the molecules the size of the molecules, their polarity (dipole moment), and their shape. ... If two molecules have about the same size and similar shape, the dipole-dipole intermolecular attractive force increases with increasing polarity.
The options are labelled as:
1 2
3 4
5 6
7 8
Protons: 1, 5, 7
Neutrons: 2, 8
Electron: 3, 4, 6