Problem Solving Module #1: Atmospheric Composition 1. The total mass of Earth's atmosphere is 5.6 x 10 km Complete Table 1-1. Hint: See Section 1.1 in textbook Permanent Atmospheric Gas Nitrogen (N) Oxygen (0) Argon (Ar) Total Mass (kg) (Scientific Notation) Percent of Atmosphere 78% 21% Total Mass (kg) (Nonscientific Notation) TABLE 1-1 2. Water vapor is a variable gas, meaning the amount that is in the atmosphere changes. Depending on the season, latitude and local conditions, water vapor may constitute up to what percentage of our atmospheric gas? Permanent & Variable Atmospheric Gases N, 0, Ar HO Percent of Atmosphere (0% H,O) 78% 21% 1% 0% Percent of Atmosphere (1% H,0) 77% 21% 1% 1% Percent of Atmosphere 12% H,O) 76% 21% 1% 2% Percent of Atmosphere (3% H,O) 76% 20% 1% 3% Percent of Atmosphere (4% H,O) 75% 20% 1% TABLE 1-2 3. According to Table 1-2. what happens to the percentage of nitrogen and oxygen in the atmosphere as the percentage of water vapor increases? An atom's "atomic mass number" is the number of protons and neutrons within its nucleus. For example, the most common form of nitrogen has an atomic mass number of 14 because it has 7 protons and 7 neutrons within its nucleus (7 + 7 = 14). The most common form of oxygen has an atomic mass number of 16 because it has 8 protons and 8 neutrons within its nucleus (8 + 8 = 16). The mass of any electron is so small that it is not factored into determining an atom's atomic mass number A subscript is the little number to the lower right of each letter. Subscripts tell us how many atoms of a particular element are present in a molecule. For example, when you breathe in oxygen (O), you are actually inhaling oxygen molecules (0.), and each oxygen molecule is composed of two atoms. When yor breathe in nitrogen (N), you are actually inhaling nitrogen molecules (N,), and each nitrogen molecule is composed of two atoms. Because a single oxygen atom (O) has an atomic mass number of 16, a single oxygen molecule (0) has a molecular mass of 32 (16+16 32). Similarly, because a single nitrogen atom (N) has an atomic mass number of 14, a single nitrogen molecule (N.) has a molecular mass of 28 (14+ 14-28).