can inorganic fertilisers be applied to the field prior to watering and ploughing it? would N be lost?

Answer 1

It is a common to broadcast fertilizer before planting with most of today's no-till or minimum tillage practices. The nutrients are soaked into the soil as they become soluble and are used by the plants as they become available. Nitrogen, however, is a different story, it will volatilize and be lost into the air if applied on top of the soil in most forms. The most common method method in agriculture today is to inject anhydrous ammonia into the soil before planting. If other forms of nitrogen such as ammonium nitrate or urea are used they should be turned under the soil.

Answer 2

Inorganic fertilizers are water soluble and are quickly absorbed by the crop.

It is not advisable to apply them before sowing unless the situation demands it ( Consult expert).

Each crop has its own specific fertilizer requirement. Do not deviate from it.

Following link will be useful -
http://extension.usu.edu/files/gardpubs/inorganic.htm