CH4(g) +2 02(g) → CO2 (g) + 2 H2O (g), how many grams of carbon dioxide are produced?

What can be added to the examples section of each circle? endothermic: ice melting into water, and a heat pack becoming warm exothermic: a glow stick glowing, and fireworks exploding endothermic: ice melting into water, and an instant ice pack turning cold exothermic: fireworks exploding, and gasoline burning endothermic: a glow stick glowing, and a heat pack becoming warm exothermic: an instant ice pack turning cold, and ice melting into water endothermic: gasoline burning, and an instant ice pack turning cold exothermic: ice melting into water, and an instant ice pack turning cold

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

The excretory system,need answers for all: )