Is it the metal in my above balanced equation ?

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The discussion revolves around balancing a chemical equation for a reaction between a metal and hydrochloric acid (HCl) to form MCl2 salts. The user balanced the equation as Mg + 2HCl → MgCl2 + H2 and calculated the moles of H+ and Mg from the given solution. They questioned whether the metal in the equation is indeed magnesium based on the mass of the residue after evaporation. Participants suggested using a generic symbol for the metal instead of Mg, as the identity is not confirmed yet. The conversation emphasizes the importance of calculating the mass of MgCl2 to verify the metal's identity.
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Homework Statement


Part one : A number of metals react with HCl to form salts of general formula MCl2.
Write a balanced chemical equation for such a reaction.

After a piece of one of these metals had reacted completely with the acid in 55.8 cm3 of 1.24M HCl, the resulting solution, which conducted electricity, was evaporated to dryness. The residue had a mass of 4.72g.

Part Two:
Part two: What is the atomic number and name of the metal?

Homework Equations


N/A

The Attempt at a Solution

So for part one I did : Mg+2HCL>MgCl2+H2

Then for part two is it the metal in my above balanced equation ? Simple yes or no answer

Thanks!
 
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Starrrrr said:
55.8 cm3 of 1.24M HCl,
Starrrrr said:
residue had a mass of 4.72g.
How many moles?
 
Bystander said:
How many moles?
H+=0.0692 moles/L and Mg=0.0346 moles
 
Can you show your work?
 
Starrrrr said:
So for part one I did : Mg+2HCL>MgCl2+H2

It would be better to use symbol Me (as in generic Metal) than Mg - at this stage you don't know the identity of the metal.

Starrrrr said:
Mg=0.0346 moles

What is the mass of 0.0346 moles of MgCl2? Does it confirm the identity of the metal?
 
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