The si standard of mass is the 1 kilogram international prototype kilogram stored in a vault in the basement of the international bureau of weights and measures in sevres, france. it is composed of an alloy that is 90% platinum and 10% iridium; having a density of 21.186 g/cm3. what is the volume of the standard kilogram?

47.201 cm^3 Remember that density is defined as mass per volume. So you can divide your known mass by your known density and get the volume occupied. So 1000 g / 21.186 g/cm^3 = 47.20098178 cm^3 Therefore the volume of the standard kilogram is 47.20098178 cm^3 Now the question is "How many significant digits do I have?". For this case, the mass of the standard kilogram is for all practical purposes known to be exactly 1 kilogram to as many significant digits as you want because it is the definition of the kilogram. So we have 5 significant figures because that's the number of significant figures we have available for the density. So round the result to 5 significant figures, giving 47.201 cm^3

Temperature and pressure