Answer: The sum of the coefficients needed to balance the combustion reaction of methane is 6.
Explanation:
Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The chemical equation for combustion of methane will be :

The coefficient foer methane is 1 , 2 for oxygen , 1 for carbon dioxide and 2 for water. The sum is 6.
Answer:
Changing the surface area from minimum to maximum increases the number of reactants in a chemical reaction.
An increase in surface area of a solid reactant means more of its particles are exposed to attack by the other Particle. This results in an increased chance of collisions between reactant particles, so there are more collisions in any given time and the rate of reaction increases.
I am 90 percent positive that the answer is the first option "Its results are inconsistent over experiments"
Answer:
c. friction between two charged particles
Explanation: