Answer:
if I knew the was a reaction taking place I would say it's lost in the atmosphere as gas
Answer:
In the option(A) moles of HCl left are 0.100 moles which is wrong, making the option incorrect.
Explanation:

Moles of HCl = n
Molarity of HCl = 1.0M
Volume of HCl solution = 30.0 mL = 0.030 L (1 mL = 0.001L)


Moles of Fe = 
According to recation , 1mol of Fe reacts with 2 mol HCl. Then 0.01 mole of Fe will recat with :
of HCl
This means that HCl uis in excess , hence excessive reagent.
Moles of HCl left unreacted :
= 0.030 mol - 0.020 mol = 0.010 mol
But in the option moles of HCl left are 0.100 moles which is wrong, making the option incorrect.
Properties of metals:
High melting points
High density
Ductile
Malleable
Good conductors of electricity
Good conductors of heat
I think if you added a proton you would have chlorine.
The noble gasses are the he chemical elements in group 18 of the periodic table. The gasses in this family include helium, neon, argon, krypton, xenon, and radon. All these gasses are colorless are oderless, elements in this family have atoms with a full outer shell of electrons. They are also called inert gasses.
Six valence electrons