Tuesday, May 19, 2015

Metal X conducts electricity when molten, has a high melting point, and reacts with dilute hydrochloric acid. Is it... A. ZINC B. SILVER C. COPPER D. POTASSIUM

Actually two of the answers are correct here.  Zinc, silver, copper, and potassium are all metals, so they all will have high melting points.  As metals, they will all conduct electricity in either the solid or liquid (molten) state.  But the final part of the question is really the key here.  Neither copper nor silver will readily react with dilute hydrochloric acid.  Zinc, however, will react with dilute HCl to form zinc chloride and hydrogen gas (H2).  The equation is given below:
Zn + 2HCl -gt ZnCl_2 + H_2
The hydrogen gas will bubble from the solution and will light a flame in a classic lab experiment.  Potassium (K) will also react with just plain water (found in dilute HCl) to also form H2:
2K + 2H_2O -gt 2KOH + H_2
So both A and D are correct here.
https://www.reference.com/science/metal-doesn-t-conduct-electricity-ddd6c5a32ea658dd

No comments:

Post a Comment

Summarize the major research findings of "Toward an experimental ecology of human development."

Based on findings of prior research, the author, Bronfenbrenner proposes that methods for natural observation research have been applied in ...