An iceberg has a volume of 8765 ft3 .
What is the mass in kilograms of the iceberg?
So we are given a volume, but they are looking for a mass. Consider the units for density, it is a mass divided by a volume. In this case, since we are working in cubic feet, our first goal is to convert this to cubic meters. To do so, we need to employ a conversion factor, which is probably in your textbook or can be found online.
To derive this is rather simple if you can wrap your head around how the units will be converted:
So, now we have a conversion factor between the volume in cubic feet and cubic meters- now we just need a density for the glacier. In this case, we must presume that the glacier is entirely composed of ice to make our calculation MUCH simpler. Looking up the density of ice is something that can be found in your textbook or with the CRC Handbook of Chemistry and Physics- which any chemistry lab will have somewhere. From the version I have on hand- the density of ice is 0.9167 grams per cubic centimeter.
Converting this to kg/m3 requires a similar procedure outlined above for converting cubic feet to cubic meters: