How many moles of sulfur are present in 2.7 moles of al2(so4)3

One mole/mol = 6.022 x 10^23 so for this all you have to do is multiply (6.022 x 10^23) x (2.7)

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock

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