Kinetics Speed by a component

If I understand correctly, the rate of the reaction is the sum of the rates by a compounds 

 Rate by a compound? Something new.

@_brauer_  Unfortunately, I don't think so. I know that you can calculate speed be a component both by products and by reagents, while you calculate speed of the reaction only using reagents 

@chaoticgood Why is it impossible to calculate the reaction rate in practice by increasing the concentration of the product?

I was talking about the mass law: v = k*[A]^n and etc

@chaoticgood Yes, thank you, I know this law. just wondering why it is impossible to measure the increase in product concentrations?

@chaoticgood Yeah, you're right. I misunderstood your first message, sorry

@_brauer_ It's OK

@argentum It's possible 

@amalgama How is this possible? Please give examples of finding the reaction rate through the concentration of the product.

Rate of the reaction May be measured by any compounds that takes place in the reaction 

That's another thing. I hope that any compounds, respectively, that are involved in the reaction, other than reaction products.

@damiryagudin So why can't you measure the rate of a reaction by changing the concentrations of the reaction products?

@argentum It is possible to calculate the reaction rate for the product. But if this is an irreversible reaction, then with an increase or decrease in the concentration of the product, the rate of the irreversible reaction will not change.