Question

Tim adds a magnesium strip to a beaker containing hydrochloric acid. He notices that bubbles immediately start to form. When the bubbling subsides, he notices that the magnesium strip is gone and that the beaker now only contains a clear solution. As the hydrochloric acid breaks apart to dissolve the magnesium, the hydrogen atoms ________ to form a ________ bond.
A) share electrons, covalent
B) exchange electrons, ionic
C) require electrons, atomic
D) combine electrons, metallic

Answer 1

The answer is A. Here is the reaction.
Mg + 2HCl ==> MgCl2 + H2
H has 1 electron and can be represented by H. as a symbol.
The other H. looks the same. They combine to form H:H. The bubbles are hydrogen gas.