The weight of an object is the gravitational force between the object and the Earth. The more mass the object has the greater its weight will be. Weight is a force, so it's measured in newtons. On the surface of the Earth an object with a mass of 1 kg has a weight of about 10 N.
One kilogram weight is that gravitational force which acts on a body of mass 1 kg.
g = 9.8 m/s2.
1 kg wt = 1 kg f = 9.8 N.
This means that the weight of 1 kg mass is 9.8 N.
(W = mg)