A scientific is based on the results of numerous experiments.

Iron reacts with oxygen to produce iron oxide (rust). this reaction is represented in an equation as 4fe + xo2 → 2fe2o3. identify the value of x that will balance the equation.

Imagine ? person stepping on a pin and pulling his or her foot way look at the réfléchir arc of the scenarios below

Where do the respiratory and circulatory systems meet? a. in the heart b. in the muscles c. in the lungs d. in the brain