Chemistry Chapter 2

Atmospheric nitrogen reacts with atmospheric oxygen to form nitrogen monoxide. Which of the following is the correct balanced equation for this process.

N2(g) + O2 (g) --> 2NO (g)

1 ppm is ____ times smaller than 1%

10,000

If air is composed of 78% nitrogen this means that by volume air contains 78 parts nitrogen for every ___ parts of air.

100

Which of the following air samples are toxic? Select all that apply. (Refer to the table provided.)

5.0 x 10^2 ug/m^3 of NO2 0.9 ppm SO2

Which of the following options describes the correct format used when writing the chemical formula of a substance? Select all that apply.

A chemical formula is a symbolic way to represent the composition of a substance. The number of atoms of a particular element is indicated by a subscript

Classify the samples of matter according to the type as indicated

A- Compound B- Element

Air/Oxygen Mixture/Pure Substance

Air- Mixture Oxygen- Pure susbtance

Describe Atoms

An atom is the smallest unit that can exist Compounds contain 2+ types of atoms Atoms are extremely small

Match each Greek numerical prefix with the correct number of atoms/entities it indicates

Di- 2 Penta- 5 Hexa- 6 Mono- 1 Hepta- 7

True of False: In order to balance the reaction of H2 with O2 to form liquid H2O a student adds a subscript of 2 to the oxygen in H2O. This is an acceptable method of balancing the reaction above.

False

Which of the following options correctly describe gases? Select all that apply.

Gases are mostly empty space Gas molecules are in constant random motion. Gas molecules are extremely small

Match each form of matter with the correct description. Mixture/Pure Substance Form of matter with a definite composition/ physical combination of two or more species

Mixture-physical combination of two or more species Pure Substance- Form of matter with a definite composition

Chemical steps in Ozone Production in order

NO2 exposed to sun, NO & O produced, oxygen atoms react to each other, Ozone is produced

During a chemical reaction, the number of different substances may or may not change, but the total mass of matter present _____.

Remains unchanged

Chemical formula for sulfur tetrafluoride

SF4

Rank the 3 pollutants listed in the table below in order of decreasing toxicity, based on the U.S. National Ambient Air Quality Standard for a 1-hour exposure period. Start with the most toxic pollutant at the top of the list.

SO2 NO2 CO

Sustainability is correctly defined as ____

meeting present needs without compromising the ability of future generations to do the same

Actions permitted in balancing chemical reaction

multiply all coefficient by a common factor odd coefficients to formulas of reactants/products

A chemical equation must be balanced. This means that the same __ and ___ of atoms must appear on both sides of the equation

number; type

A molecule that always contains carbon and may contain hydrogen, oxygen, and nitrogen is called a(n) _____ compound.

organic

A(n) ___ pollutant is produced from chemical reactions involving one or more other pollutants.

secondary

The common name for the compound H2O is ___, while the compound NH3 is commonly known as _____.

water, ammonia