@ferdinard, wen an object does nt experience gravity , it does nt come down, if it doesn't come down, it has no Weight, but it still has its mass..... @desire 4get d daily misconception of mass and weight, mass is measured in kg, while weight is measure in kg/m^2 or newton(N), if a stone of 10kg is thrown into d atmosphere of earth with gravitational force to b 9.8,its weight wud b 10x9.8 = 98kg/m^2 or N, but if d Same stone is thrown up into a planets atmosphere or space with 0 gravity, it's weight wud b 10x0=0 kg/m^2 or N, but 4 simplicity, weight both on measuring instruments and measured items ar calibration in kg only.....
Hence d mass of a bag of cement is 5kg......... Recall Dat kg is a fundamental unit