Hi..
I have a project that needs to detect monochrome color from a distance of about 2.00 meters.
What sensor serves me in this case?
Please explain what you mean by "monochrome color".
It means that following..
The basic color is white ( background)... If interrupted ( changed) with any contaminant ( object or color variant) it give a signal or alert.
It depends on how bright this light is.
Colour sensors I have seen will not be sensitive enough at this sort of distance.
I don't think you'll find one with this much sensitivity.
Hi,
It would be best for you to tell us your project, what is the application?
Then we can provide some possible answers.
At the moment, in plain language, it sounds like you want to detect light beam being broken.
Thanks.. Tom... 
The project is as following..
We have plain white cups that contains pure transparent fluid (water).. I want to detect if there is a change in the fluids color ( tea, coffee, juice etc..).
The distance is about 2 meters.
I don't need to detect the type or intensity of color.
What I want is a signal that tills me if the fluid still clear or not ( white or not).
Thank you in advance 
Arduino, IMO, is not the right platform because the 200 centimeters implies a color sensor with a narrow viewing range, thus optics become a concern. As mentioned earlier, light intensity is a concern.
Rather, the application of AI training with a camera sensor leads one away from microcontrollers and into SoC territory such as Raspberry Pi where such scenarios are more straightforward.
Just my 2-cents.
Added:
State of Arduino color
iD from hobby pov:
Overview | Adafruit Color Sensors | Adafruit Learning System
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In any arbitrary situation, or are the bottles confined to some "gate" like a certain position on a conveyor belt or dispenser? Why 2.0 meters?
Did you mean clear, transparent plastic or glass cups? White paper cups would not work well.
No.. It is like a coffee machine without any color coding for the outer pack
Is the illumination of your thing also monochrome? The illumination will be the light your sensor sees. The illumination also needs to contain the colors of your contamination, so the light must be multi-chromatic light.
So you are looking at a reflective level from the surface of the container, not a level "transmitted" by a source on the other side of the container?
I would think you will be looking for a sensor that has a focusing lens to make use you are looking at the container and NO surrounding area, to make sure your "reflected" signal is detected.
Why 2.00m?
Thanks.. Tom.. 
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Well, in a dispensing coffee machine the target is confined to a gate. It's the filling platform.
Please provide a lot more details, generally. Otherwise this becomes a tedious guessing game.
I have managed to reduce the distance to become (25-30 cm)..
Do you have any idea about such a color sensor that recognize colors from this distance
You are still playing the game, "great wizard of oz", where the actual machinery is hidden from us. Of course it is not just about distance - it matters what the environment is, what the path is, what is behind it, what ambient light conditions are, and more.
I'm not sure if this behaviour is deliberate or not, but it isn't productive in finding a solution to your problem.
Are you asking people to test the sensors for you, or have you tested ANY sensors, yet?
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The common sensors that i found( TCS3200, TCS3414, TCS34725) have just a sensitivity of 1 to 5 cm.
Did you try any with brighter illumination?
Light sensitivity is not measured in centimeters. You probably mean that with a typical arrangement of sensor and target, that is the range. If you put some optics on them, you could probably extend the range considerably. But again, you are holding details on that "close to your chest". So if you don't come back now with some real information, I'm going to block you so I don't waste any more time on you in the future.