Well you know that you have to balance out the equation to 0. So if I is -1 and Ca is +2 you know that I had to equal to -2. So you can do that by having two of them. So Ca=+2 and I2=-2 so CaI2 would equal 0 meaning that would be the correct answer. Hope that I explained that correct :)
Answer:
Place the reactants in a smaller container.
Explanation:
If you were to reduce the source of heat, the hydrogen and oxygen molecules would lose their kinetic energy, resulting in less collisions.
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Maintaining the same temperature of the reactants, the speed would neither increase nor decrease as temperature is directly proportional to the kinetic energy of the molecules, which in turn is directly proportional to the number of collisions. However, placing the reactants in a smaller container would result in less volume, and hence the molecules would collide with one another more often!
<u><em>Hope that helps!</em></u>
