Which of the following attractive forces would result in the lowest melting point?
a. van der waals forces
b. dipole-dipole attractions
c. hydrogen-bonding forces
d. ionic electrostatic attractions

the answer is:  

line graphs show patterns in data with variables that change over time; whereas, circle graphs show data as parts out of a whole (such as out of 100%).

the dissociation of nickel hydroxide is follows:

the concentration of hydroxide ion is

the equilibrium constant value of nickel hydroxide is = 6.1 * 10^-^1^6 and thus equilibrium equation can be written as:

thus, concentration of ni is 0.23 * 10^-^4 mol /l