As a general estimate, you can expect approximately 5 to 10 kilometers per kWh. This means that an electric car with a battery capacity of 40 kWh, under ideal conditions, would have a range of about 200 to 400 kilometers.

It's important to remember that this is just an estimate and that the actual range can vary. Factors such as the use of air conditioning or heating, driving at high speeds, hilly terrain, and carrying extra loads like passengers or luggage can all affect the actual range of the electric car.

To get a more accurate picture of the range of a specific electric car, it's best to look at the specifications and information provided by the manufacturer, as well as the data and experiences of other owners of similar models.