Idon't get balancing chemical equations, can someone explain?

Use examples from the article to explain one positive and one negative effect that chemistry has had on society.

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.

Why do oxygen have a strong attractive force for electrons