Different worksheets on different screens

I now have two screens on my desk linked to the same computer. Working in Excel I would like to open a new worksheet on one screen and an existing worksheet on the other screen. However, when I try to do this it just makes one replace the other. Am I missing something simple or can it not be done?

All comments gratefully appreciated.

You need to set up your graphic card configuration to expand your desktop on both screens. You then open a second instance of Excel and drag it to the other screen. I have Win 7 with Excel 2010, and this works for me. To open a second instance with Win 7, you open Excel and then right click on the Excel tab on the task bar at the bottom and select Microsoft Excel 2010. This will open a second instance of Excel ready to me moved to the other screen if needed.