Which of these elements exists as a solid at room temp and pressure? chlorine, bromine and iodine. why?

If a solution is considered basic, then a) the hydroxide ion and hydronium ion concentrations are equal. b) the hydroxide ion concentration is less than the hydronium ion concentration. c) the hydronium ion concentration is greater than the hydroxide ion concentration. d) the hydroxide ion concentration is greater than the hydronium ion concentration.

In which situation can a mixture always be called a solution

What is the mass of 0.46 mol of mgcl2