If 87.45 kg of an alloy was formed when 81.25 kg of iron mixed with nickel. how many pounds of nickel were used?1.37*10^1 lbs. math unknown, show.

13.7 lbs Since the assumption is that the alloy consists only of nickel and iron, the mass of the nickel will be the total mass of the alloy minus the mass of the iron. So 87.45 kg - 81.25 kg = 6.2 kg Now we need to convert from kg to lb using the conversion factor of 2.20462 lb/kg. So 6.2 kg * 2.20462 lb/kg = 13.668644 lb. Rounding to 3 significant figures gives 13.7 lb of nickel was used.

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.