Which of these is a mixture?

a. oxygen
b. air
c. carbon dioxide
d. carbon

Answer is: b. air.

Homogeneous mixture (air) has the same proporties of its components (nitrogen, oxygen, carbon dioxide) throughout any given sample.

Together, nitrogen (N₂) and oxygen (O₂) by volume account for 99,03% of the gases composing the dry air in the lower atmosphere.

Volume of nitrogen in air is 78,08%.

Volume of oxygen in air is 20,95%.

Together: 78,08% + 20,95% = 99,03%.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.