The untrue statement is that they high melting points.
The covalent compounds are the compounds exhibiting strong intra-molecular bonds. This is due to the tightness of the atoms within the covalent molecules. The force of attraction between the individual molecules in a covalent compound seems to be weak. The covalent compounds exhibit weak intermolecular forces that hold the atoms together due to this they have a low melting point.
The balanced equation for the above reaction is as follows;
C + H₂O ---> H₂ + CO
stoichiometry of C to H₂O is 1:1
1 mol of C reacts with 1 mol of H₂O
we need to find which is the limiting reactant
2 mol of C and 3.1 mol of H₂O
therefore C is the limiting reactant and H₂O is in excess.
stoichiometry of C to H₂ is 1:1
then number of H₂ moles formed are equal to C moles reacted
number of H₂ moles formed = 2 mol
Putting glue on something, because once it is set in you cannot change it back.