Many early balloonists dreamed of completing a trip around the world in a hot-air balloon, a goal not achieved until 1999. Write about what you imagine a trip in a balloon would be like, including a description of how manipulating air temperature would allow you to control your altitude

Factor Label Method In a laboratory, $400 \mathrm{~L}$ of methane are stored at $600 \mathrm{~K}$ and $1.25 \mathrm{~atm}$. If the methane is forced into a 200-L tank and cooled to $300 \mathrm{~K}$, how does the pressure change?

How does an increase in atmospheric pressure affect the following? (Chapter 10) a) the boiling point of water b) the melting point of ice

Classify the following bonds as ionic, covalent, or polar covalent using electronegativity values. (Chapter 9 ) a) $\mathrm{NH}$ c) $\mathrm{BH}$ b) $\mathrm{BaCl}$ d) $\mathrm{NaI}$

Can an atom of an element have six electrons in the $2 p$ sublevel?

What are allotropes? Name three elements that occur as allotropes.

How can a reaction be slowed down?

a) add an inhibitor

b) increase the activation energy

c) add more reactants

d) all of the above

A cylinder containing $32 \mathrm{~g}$ of oxygen gas is placed on a balance. The valve is opened and $16 \mathrm{~g}$ of gas are allowed to escape. How will the pressure change?

Use Boyle's law to predict the change in density of a sample of air if its pressure is increased.

Automobile tires become underinflated as temperatures drop during the winter months if no additional air is added to the tires at the start of the cold season. For every $12.2^{\circ} \mathrm{C}$ drop in temperature, the air pressure in a car's tires goes down by about $1 \mathrm{psi}(14.7$ psi equals $1 \mathrm{~atm})$. Complete Table. Then make a graph illustrating how the air pressure in a tire changes over the temperature ranges from $5^{\circ} \mathrm{C}$ to $-25^{\circ} \mathrm{C}$, assuming you start with a pressure of $30.0 \mathrm{psi}$ at $5^{\circ} \mathrm{C}$.

MiniLab 2 Explain how air pressure helps you transfer a liquid with a pipet.

MiniLab 1 How might you account for the possible popping of the bag containing the subliming dry ice?

ChemLab How are inferences made about the relationship between volume and pressure in this chapter's ChemLab similar to inferences made from observing the apparatus described in Figure ?

Would chlorine gas be suitable for weather balloons? Explain.