An is a substance that protects vulnerable molecules from free radicals.

Asmall amount of a solid is added to water. the observation made after fifteen minutes is shown in the figure. which of these solids has been probably added to water? a) oil b) sand c) sugar d) wood chips

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture

How much energy is made when a pice of wood burns. how do you know