List at least one reason for not touching the magnesium metal with bare hands. 3. list two reasons for using crucible tongs to handle the crucible and lid after their initial firing in the experimental procedure.

Crucible tongs are mandatory to handle hot crucibles to avoid skin burns and accidents during experimental procedures. Crucible tongs work with the crucible; their shape was designed to firmly hold it to avoid spills.

Touching the magnesium metal can actually contaminate it and bring with it impurities which may not be removed by heating. So this leads to error in weighing.

There are two reasons not to touch the crucible tong with bare hands:

1. The crucible tong is used during firing so it is extremely hot and may burn your hands

2. Any impurities in your hand may contaminate the tong hence leading to error just like the case for the magnesium metal

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.