7. Which substance can be decomposed by a chemical change? * a. carbon
b. boron
c. magnesium
d. methanol

8. Which substance cannot be decomposed by a chemical change? *
a. water
b. carbon
c. citric acid
d. carbon dioxide

Amixture with the same composition throughout is!

The diagram shows the relationship between scientific disciplines.the names of some scientific disciplines have been removed from the boxes. which scientific discipline belongs in the blue box? a.physics b.biology c.chemistry d.metallurgy

The equation below shows a chemical reaction. a + b + heat —> c + d according to the law of conservation of energy, which statement is true? a. the reactants absorb heat because they have less energy than the products. b. the products release heat because they have more energy than the reactants. c. the reactants generate heat because they have more energy than the products. d. the products require heat to form because they have less energy than the reactants.