Which of these reactions is a combustion reaction?

a. burning wood
b. decomposition of water
c. production of food by plants with the of the sun's energy
d. rotting of fruits and vegetables

Using the periodic table, complete the table to describe each atom. type in your answers. a ? b? c? d? e? f?

Which statement is true about a catalyst? a: a catalyst decreases the rate of the reaction. b. a catalyst is consumed during a chemical reaction. c. a catalyst lowers the activation energy of a reaction. d. a catalyst increases the reactant concentration during a reaction.

Suppose you mix one mole of sulfuric acid (h2so4) with 1 mole of sodium hydroxide(naoh). why does the ph of the solution remain below 7? ( explain so i can get better understanding! )