All of the following require breaking and forming chemical bonds except
a. burning coal
b. rusting iron
c. evaporating water
d. tarnishing silver

Write the complete balanced equation for the reaction between lead (iv) oxide (pbo2) and water (h2o).

This line graph compares the growth of plants that were kept in the sun for different amounts of time.a)  on day 7, the plants kept in the sun for 3 hours were how tall? b)  on day 7, the plants kept in the sun for 6 hours were how tall? c)    on day 10, the plants kept in the sun for 9 hours were how tall? d)  on day 11, the plant that was grown with 1 hour of sunlight was how tall? e)  based on the graph, the plant grows best in what amount of sunlight?

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