You and your friend live in different states and plant identical hydrangea bulbs in your garden. when they bloom, you send each other pictures. you notice that even though you bought the exact same kind of plant, your hydrangea flowers are blue and your friend’s are pink! on a hunch, you each measure the ph of your soil and find that your soil is a little acidic and your friend’s is a little basic. why do you think the flowers have different colors?

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Achemical reaction (also known as a chemical change) produces substances that are chemically different from the starting materials. an example of a chemical reaction is the formation of water from hydrogen and oxygen gas. in a physical change, a substance changes its physical appearance but not its chemical identity. an example of physical change is the formation of liquid water from solid water, a familiar process called melting. physically, liquid water looks very different from solid water (ice) but the chemical identity, water, is the same for both. which of following changes that affect the composition of our atmosphere involve physical changes and which involve chemical reactions? oxygen gas changes to ozone during thunderstorms carbon dioxide is produced by the combustion of gasoline in an automobile engine. when coal, oil, and natural gas are decomposed in landsills they produce methane gas. freezing rain develops when a warm air mass overrides a cold air mass. fog forms from water vapor when the temperature drops below the dew point

Compared with the freezing-point depression of a 0.01 m c6h12o6 solution, the freezing-point depression of a 0.01 m nacl solution is

The name of the ion, s2-, is: sulfurous ion sulfide ion sulfur ion sulfate ion