chem help ;/?

Question

i have no clue how to find the answer. i googled and everything.

"explain why magnesium metal, rather than copper metal, might be used to study the effect of concentration of hydrochloric acid on rates of reaction."

any help would be highly appreciated, thanks.

Answer 1

Because magnesium is more reactive than copper, a reaction will be more clear to see as more hydrogen will be created & released as bubbles.

Answer 2

Magnesium metal is more reactive than copper in reacting with hydrochloric acid to produce hydrogen gas which can be easily measured. Moreover, the reaction essentially goes to completion, that means all of the magnesium is consumed confirming the molar ratios in the balanced equation. On the other hand, the reaction of copper will take so much time to even be of practical value if you want results right away.

In a reaction rate experiments one must be able to change the acidity INSTANTLY. The use of magnesium does this nicely and fast in contrast to copper. This is on the assumption that the presence of Magnesium ions do not affect the reaction rates.

Having said that, I would not particularly use the method you have said because a) magnesium metal reacts with air, causing already an inherent determinate error unless you do the experiment in an inert atmosphere! which is also hard to do.
b) the reaction of magnesium with HCl can be explosive (depending on the amounts used) and therefore inherently has safety drawbacks.


There are a lot more benign and efficient ways of determining the concentration of HCl to check its effect on the rates of reaction.

Answer 3

Magnesium also reacts with hydrochloric acid and produces heat and a gas when added to it. The magnesium will begin to bubble and become hot, too hot to touch comfortably.The reaction will occur faster with higher temperatures (see precautions). Magnesium is a highly flammable metal, but while it is easy to ignite when powdered or shaved into thin strips, it is difficult to ignite in mass or bulk.

copper doesn't have the same reaction,like mangesium

Answer 4

Magnesium only has one oxidation number while copper has many.

What this means is that copper could bind with multiple ligands - in other words, it can bind with 2, 3, 4, etc other things. So if a copper solid precipitates out, you don't know exactly how many ligands it picked up.

Magnesium on the other hand has a set number of bonds that it can make. When a magnesium solid precipitates out, you know that it only bonded with two other things.

Answer 5

Copper tends to form a protective layer (patina) which might obscure the results by blocking some of the copper from reacting. Aluminium does something similar.

Answer 6

thank u for da potassium answer and good luck with this