Study the reaction. X(s) + 2B(aq)→ X+(aq) + B2(g) Under which circumstances will the reaction rate be highest? A) the solid X is ground to a fine powder B) the solid X is in the form of a few smooth spheres C) the solid X is densely packed at the bottom of the container D) the solid X is in the form of a single, large cube.

Option (A) the solid X is ground to a fine powder.

Explanation:

X(s) + 2B(aq) → X+(aq) + B2(g)

In the reaction above, the rate of the reaction will be highest, when X being a solid is ground to fine powder.

Grounding X to fine powder simply means increasing the surface area of X.

An increase in surface area of reactants will definitely increase the rate of reaction because the particles of the solid will collide with the right orientation and hence speed up the reaction rate.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-