A metal (M) completely reacts with $34.8mL$of a $0.520M$$HCl$solution to form $MC{l}_3$and $H_2$.

a. Write the balanced chemical equation for the reaction of the metal and $HCl$

b. What volume, in milliliters, of $H_2$produced at STP?

c. How many moles of metal M reacted?

d. If the metal has a mass of $0.420g$, use your results from part c to determine the molar mass of the metal M.

e. What are the name and symbol of metal M in part d?

f. Write the balanced chemical equation using the symbol of the metal from part e.

We are given that a metal reacts with with $HCl$.

As we know, the metal is reacting with $HCl$, therefore, the balanced chemical reaction is $2\mathrm{M}\left(\mathrm{s}\right)+6\mathrm{HCl}\left(\mathrm{aq}\right)\to 2{\mathrm{MCl}}_3\left(\mathrm{aq}\right)+3{\mathrm{H}}_2\left(\mathrm{g}\right)$

We are given that a metal reacts with with $HCl$.

From above equation We can say millimoles of$HCl$ is two times millimoles of $H_2$

And we also know volume at STP is $22.4L$

Therefore, volume of $H_2$produced at STP is $203mL$

We are given that a metal reacts with with$HCl$

From the balanced equation, We can say that millimoles of metal is equal to three times millimoles of $HCl$.

millimoles of $HCl$is product of molarity and volume Therefore,

millimoles of $HCl$is $M_1{V}_1=34.8\times 0.520=18.096$

So, millimoles of metal is $\frac{1}{3}{M}_1{V}_1=\frac{1}{3}\times 18.096=6.03$

Hence, Moles of metal is $6.03\times {10}^{-3}$

We are given that a metal reacts with with $HCl$.

As given mass of metal is $0.420g$

Moles of metal is $6.03\times {10}^{-3}$

Molar mass is $\frac{givenmass}{numberofmoles}=\frac{0.420}{6.03\times {10}^{-3}}=69.7g/mole$

We are given that a metal reacts with with $HCl$.

From above part , we can say the name of metal is Gallium and its symbol is $Ga$.

We are given that a metal reacts with with $HCl$.

As we know from part(e) that the metal is Gallium.

Therefore, by replacing metal in first equation by gallium.

So, the balanced equation is : $2Ga\left(s\right)+6HCl\left(aq\right)\stackrel{}{\to }2GaC{l}_3\left(aq\right)+3H_2\left(g\right)$