The unit of mass is the kilogram which is defined as the mass of the international prototype kilogram maintained at the international bureau of weights and measures ( bipm ) in france 質(zhì)量質(zhì)量的單位是千克,其定義為在法國的國際計量局( internationalbureauofweightsandmeasures )所持的國際公斤原器( internationalprototypekilogram )的質(zhì)量。