Christopher berg land holds the world record for most distance run on a treadmill in day. He ran 247.54 km. How many miles per hour did Chris have to run to accomplish this? note: Can you please explain how to do this and not just give the answer?

6.408924056 miles/hour.

Explanation:

First we have to convert 247.54 km to miles. The conversion factor will be 1 km = 0.621371 miles. To do this I set up my stoichiometry.

247.54km | 0.621371miles = 153.8141773 miles

                 |  1 km

Now we have 153.8141773 miles per 1 day. The conversion factor will be 1 day = 24 hours.

153.8141773 miles | 1 day       6.408924056 miles/hour.

1 day                      | 24 hours

(if you need to know what I did with the stoichiometry just ask! I'll be happy to help!)

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g