How many of the following responses are true? 1. sn1 leads to a racemization of sterechemistry due to the planar carbocation intermediate 2. sn2 leads to a racemization of sterechemistry due to the planar carbocation intermediate 3. a tertiary alkyl halide will tend to react through an sn2 mechanism because there is little hindrance to backside attack and a tertiary carbocation is not very stable 4. 1-bromopentane will undergo substitution through an sn1 mechanism 5. if r-3-bromo-3-methylhexane is allowed to react with oh- the product will be a 50%/50% mixture of r-3-methyl-3-hexanol and s-3-methyl-3-hexanol

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

Read the chemical equation. 2c2h2 + 5o2 → 4co2 + 2h2o which of the following statements would be correct if one mole of c2h2 was used in this reaction? one mole of oxygen was used in this reaction. five moles of oxygen were used in this reaction. four moles of carbon dioxide were produced from this reaction. two moles of carbon dioxide were produced from this reaction.

Describe what happens to the molecules as water goes from ice to liquid to vapor. be sure to explain what happens to the temperature during the phase changes.