You are confronted with an unknown metal, M, and need to determine its identity. Using the following information identify the metal.
M(s) Reacts vigorously with water and acid.
M(s) does not react with K+(aq)
M(s) reacts with Co+2(aq)
M(s) does not react with Ca+2(s)
M(s) reacts with Na+(aq)
A metal that reacts vigorously with water must belong to Groups I-A (alkalis) or II-A (alkaline earths). Not reacting with K+ and Ca^+2 is no help at all. Not many other species do, either. Besides, Ca+2(s) is pure nonsense. Reacting with Na+ is unlikely. Reaction with Co+2(aq) is no help either since a Group I and II metal would react with water rather than a transition metal ion.
It is not possible to give a good answer to a bad question, no matter how many times you post this.
To identify the unknown metal M, we need to analyze the given information about its reactions with different substances. By comparing the observations with known properties of metals, we can deduce its identity.
Let's break down the given information:
1. M(s) reacts vigorously with water and acid: This suggests that M is a reactive metal. Reactive metals like sodium, potassium, and calcium react with water and acids to produce hydrogen gas.
2. M(s) does not react with K+(aq): This indicates that M is not potassium since it does not react with K+(aq).
3. M(s) reacts with Co+2(aq): This suggests that M can displace cobalt from its aqueous solution. This behavior is typical of highly reactive metals that lie above cobalt in the reactivity series.
4. M(s) does not react with Ca+2(s): This implies that M is not calcium since it does not react with Ca+2(s).
5. M(s) reacts with Na+(aq): This indicates that M is similar to sodium since it reacts with Na+(aq).
Based on these observations, we can conclude that the unknown metal M is most likely sodium (Na). Sodium reacts vigorously with water and acids, can displace cobalt from its aqueous solution, and reacts with Na+(aq). It is consistent with all the given information.
So, the identity of the unknown metal M is sodium (Na).