I think money represents wealth.
But it is not wealth.
If somebody makes 5 dollars and another one makes 10 dollars, it means that the second creates twice as much wealth as the first (or at least that is how the market perceives the value of their production).
If a minimum wage law increases the 5 dollars to 6, it does not actually increase the wealth produced. Since money is not wealth but merely represents wealth, all that the law did was change the numbers, i.e. the units of measurement.
The market will, as Jill pointed out, adapt and our 10 dollar employee will soon make 12 dollars. And the 12 dollars will by what the 10 dollars used to buy. The result is inflation. And that's it. The process is also inefficient, which means that society will also lose some wealth (namely the resources required for distributing the measurement change and what the market loses when adapting the inflation rate).
Let me give a non-monetary example, which is perhaps easier to understand.
Length can be measured in many ways, but we can measure them, here, in a made-up unit called "toes". Let's say we have to runners, Dave and Floyd. Dave walks 500 toes a day, Floyd walks 1000 toes a day. (They have to keep fit. They are both overweight, especially Dave.)
Now the doctor (they have the same doctor because of socialised medicine, or perhaps they just chose the same one, I don't know) tells them that 1000 toes is enough, but 500 toes is NOT enough. Dave must walk more because he does not walk enough. Dave must walk 600 toes a day.
But Dave is not capable of walking more than 500 toes, because he is lazy and unqualified or unlucky (or one or two of the three).
The government steps in. The government look at the distance Dave walks every day (the wealth he creates) and decides to call it "600 toes". (Remember that "toes" is our unit of measurement. A "toe" is not a distance, it represents a distance.)
Problem solved.
But no, not really. Turns out Dave's body still thinks that the distance is really the same. And in contrast to the market, it cannot be cheated, not even for a year or so. Plus Floyd suddenly finds himself walking 1200 toes instead of 1000, even though he still walks the same actual distance. (In mathematics changing the unit travels faster than in the market.)
And Dave suddenly realises (or actually, others realise it for him) that 600 toes is not what he needs, he needs to walk more. Changing the unit did not help, as he still walks (creates wealth) half as much as Floyd.
Dave should walk at least 60% of the distance Floyd walks. That would be healthy. Forcing him to walk more would help. Changing the unit does not. But forcing him to work harder is not feasible in a free society. So perhaps Dave will simply have to learn that unless he creates more wealth (walks more) he will not become more wealthy (more healthy).