One of the challenges astronauts face is in space travel is the build-up of carbon dioxide in their spacecraft. The average human exhales about
42.0 g of carbon dioxide per hour. One method to remove the excess
carbon dioxide from the air is using solid lithium hydroxide:
CO2(8)
+
2 LiOHs
-
Li2CO3(2)
+
H2O(1)
If a typical cannister of LiOH contains 750.0 g, how many hours will
it last for one person before it has to be replaced?

Which of the following will cause an increase in the acceleration of an object? increase force decrease force increase mass decrease mass

1.) which of the following is a molecule but not a compound? a.he b.f2 c.h2o d.ch4 2.) what is a physical combination of substances? a.a compound b.a molecule c.a mixture d.an element 3.) what is a chemical combination of substances? a.a compound b.an atom c.a mixture d.an element 4.) what is the relationship between the solute and solvent in a solution? a.they form a compound b.they form a mixture c.they form molecules d.they form chemical bonds 5.) the gases in air dissolve in water. what would be one way to reduce the amount of a gas dissolved in water? a.add more water b.reduce the air pressure c.increase the air pressure d.stir the water 6.) how would you determine the solubility of a substance? a.find how well it dissolved various substances. b.find the mass and the volume of the substance. c.find the temperature at which the substance evaporated. d.find how much i was able to dissolve in a solute. 7.) the periodic table organizes all of the kinds of a.molecules. b.compounds. c.atoms. d.ions. 8.)what distinguishes two substances combined to become a compound vs. two substances combined to become a mixture? a.whether they can be easily separated b.whether they chemically bond together c.whether they both are visible d.whether they are heterogeneous 9.) the principle components of air are: n2 78% o2 21% ar 0.95% co2 0.038% this is a solution of a.molecules and atoms. b.molecules. c.compounds and molecules. d.atoms.

What is the significance sodium hydroxide and hydrochloric acid