What is true for water?

A) In a phase diagram the solid-liquid coexistance line has a negative slope.
B) In a phase diagram the solid-liquid coexistance line has a positive slope.
C) The solid is more dense than the liquid.
D) The solid is less dense than the liquid.
E) The molecules are closest in the solid phase.
F) The molecules are closest in the liquid phase.
G) High pressure will cause the solid to become liquid.
H) High pressure will cause the solid to become solid.

I got G, F, E, and C but it is wrong.

To determine the correct options, let's analyze each statement one by one:

A) In a phase diagram, the solid-liquid coexistence line refers to the boundary between the regions where both solid and liquid water can exist simultaneously. The slope of this line describes the relationship between temperature and pressure.

To check if the statement is true, you can look up a phase diagram of water or use the phase diagram equation:

(Temperature at which ice melts under a given pressure) - (Temperature at which ice melts under a lower pressure) / (change in pressure) = slope.

B) This statement is the opposite of option A and suggests a positive slope for the solid-liquid coexistence line.

C) Water is known to be an exception to the general rule that solids are denser than liquids. In the case of water, the solid phase (ice) is less dense than the liquid phase. This fact is responsible for the phenomenon of ice floating in water bodies.

D) This statement suggests that the solid phase is more dense than the liquid phase, which is incorrect.

E) In the solid phase, water molecules form a regular lattice or a repetitive geometric pattern. This arrangement of molecules in a solid makes them relatively closer compared to their arrangement in the liquid phase, making this statement true.

F) In the liquid phase, water molecules have more freedom to move and are not held in a fixed structure like in the solid phase. This lack of fixed arrangement leads to a relatively greater average distance between water molecules, making this statement false.

G) High pressure typically destabilizes the solid phase and promotes the transition to the liquid phase. This is evident in water, where increasing pressure can cause the solid ice to melt into liquid water, making this statement true.

H) High pressure does not cause a solid to become solid, so this statement is false.

After reviewing each statement, the correct options are:

A) In a phase diagram, the solid-liquid coexistence line has a negative slope.
G) High pressure will cause the solid to become liquid.

Therefore, the correct answer is A and G.