The decomposition of water into hydrogen gas H2 and oxygen gas O2 can be modeled by the balanced chemical
equation
A. H₂ + O₂ -> H₂O
B. H₂O -> H2 + O2
C. 2H₂ + O₂ → 2H₂O
D. 2H₂O → 2H₂ + O2

Kinetic energy = 1/2mv^2. since the mass is constant we can form a ratio of it's kinetic energy at 60 divided by that at 30 to see ke(60)/ke(30) = +(60^2)/30^2). this may be said to 300% increase.

The correct answer is c. hope this

Iwould have to say sorry i can't elaborate more. hope this though!