Hi Vasu
This is a classic case. A window near the cooking hob is always tricky. We had discussed this on the blog sometime back.
http://aavaas.com/2007/10/05/hob-placement-in-kitchen-user-query/http://aavaas.com/2007/10/11/hob-placement-in-kitchen-user-query-part-2/If you apartment is still in construction phase, you could arrange the vent for the chimney in a concealed manner.
Coming to your query - Sliding windows and normal swing open windows, both pose cleaning problems and this is heightened by the fact that you are cooking right under it.
The chimney i most effective when place about two or three feet on top of the cooking stove. If you do this, your window is going to be blocked too.
I could suggest that you have the hob and the chimney adjacent to the window if possible. Do you have some drawings which we could see?