If naturally occurring Iron has a percent abundances of 80% Fe-56 atoms and 20% Fe-55 atoms. What is it's atomic mass?

The data below were determined for the reaction shown below. s2o82– + 3i – (aq) → 2so42– + i3– expt. # [s2o82–] (m) [i –] (m) initial rate 1 0.038 0.060 1.4 × 10 – 5 m/s 2 0.076 0.060 2.8 × 10 – 5 m/s 3 0.076 0.030 1.4 × 10 – 5 m/s the rate law for this reaction must be:

A250 g sample of water with an initial temperatureof 98.8 closes 6500 joules of heat. what is the finaltemperature of the water?

In a 28 g serving of cheese curls there are 247mg of sodium. how much sodium is in a 12.5 ounce bag