The pressure 75.0 meters underwater is 837 kpa. what is this pressure in mmhg

                 6278 mmHg

Kilopascal (kPa) and Millimeter of Mercury (mm Hg) are both the units of Pressure. In medical science the pressure is often measured in mm of Hg.

Also,

                 0.133322387415 kPa equals  =  1 mmHg equals

Then,

                       837 kpa will be equal to  =  X mmHg

Solving for X,

                     X =  (837 kPa × 1 mmHg) ÷ 0.133322387415 kPa

                     X  =  6278.0153898 mmHg

Or when rounded to 4 significant numbers,

                     X  =  6278 mmHg

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 !