Take the attached picture of a periodic table as a guide. You are finding for a solid metal. Therefore, streamline your choices by looking at elements written in black bold letters, because they are all solid. Next, if you look at the center, the legend for metals are colors in orange, yellow, flesh, lavender, pink, and cyan blue. These region would be your choices. Next, you want to find a metal that is shiny and ductile. The shiny appearance is a common characteristic of luster by materials. Ductility is the ability of a metal to stretch when under tensile stress. These properties are best exhibited by metals in the transitions metals colored in pink. Therefore, the answer to your question would be any of the metal in the pink area. Examples are Titanium, Chromium, Gold, Silver, Platinum, Tungsten, etc.
Air is a mixture, Its constituens can be seperated
"A contactor is a electrically controlled switch which uses an electromagnetic coil to pull in the contacts.”
"A motor starter is a contactor, plus an overload relay that will drop out the coil voltage if the motor overloads. If there is not overload relay, it is not a starter any longer, it's back to being just a contactor."
In a dilute acid solution most if not all of the molecules will split into ions.
For example HCl is a strong acid and 100% of the molecules will split into
H+ & Cl-
in a weak acid solution only a portion of the molecules will turn into ions because the ionization percentage isn't as large. Which will essentially leave a high percentage of un-reacted molecules