An atom of krypton has a radius rKr = 88. pm and an average speed in the gas phase at 25°C of 172.⁢/ms. Suppose the speed of a krypton atom at 25°C has been measured to within 0.010%. Calculate the smallest possible length of box inside of which the atom could be known to be located with certainty. Write your answer as a multiple of rKr and round it to 2 significant figures. For example, if the smallest box the atom could be in turns out to be 42.0 times the radius of an atom of krypton, you would enter "42.rKr" as your answer.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.