Which of the following is not evidence of a chemical change? a. a change in color b. the production of a gas c. the formation of a precipitate d. the separation of particles

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?

What is conserved in the reaction shown below? h2(g) + cl2 (g) --> 2hcl(g)a. mass onlyb. mass and moles onlyc. mass, moles, and molecules onlyd. mass, moles, molecules, and volume

Which of the following is not true about the atomic model of substances?