Consider the reaction below. 4Fes2 + 11O2 —> 2Fe2O3 + 8SO2
If the reaction produces 2.00 moles of Fe2O3, when 7.55 moles of O2 react, what is the percent yield of the reaction?

3. 68.55 g

4. 145.99%

Explanation:

3. Determination of the actual yield of NO.

4NH₃ + 5O₂ —> 4NO + 6H₂O

Next, we shall determine the mass of NH₃ that reacted and the NO that reacted from the balanced equation. This is illustrated below:

Molar mass of NH₃ = 14 + (3×1)

= 14 + 3

= 17 g/mol

Mass of NH₃ from the balanced equation = 4 × 17 = 68 g

Molar mass of NO = 14 + 16

= 30 g

Mass of NO from the balanced equation = 4 × 30 = 120 g

Summary:

From the balanced equation above,

68 g of NH₃ reacted to produce 120 g of NO.

Next, we shall determine the theoretical yield of NO. This can be obtained as follow:

From the balanced equation above,

68 g of NH₃ reacted to produce 120 g of NO.

Therefore, 45.7 g of NH₃ will react to produce = (45.7 × 120)/68 = 80.65 g of NO.

Thus, the theoretical yield of NO is 80.65 g

Finally, we shall determine the actual yield of NO. This can be obtained as follow:

Percentage yield of NO = 85%

Theoretical yield of NO = 80.65 g

Actual yield of NO =?

Percentage yield = Actual yield /Theoretical yield × 100

85% = Actual yield / 80.65

85/100 = Actual yield / 80.65

0.85 = Actual yield / 80.65

Cross multiply

Actual yield of NO = 0.85 × 80.65

Actual yield of NO = 68.55 g

4. Determination of the percentage yield.

4FeS₂ + 11O₂ —> 2Fe₂O₃ + 8SO₂

From the balanced equation above,

11 moles of O₂ reacted to produce 2 moles of Fe₂O₃.

Next, we shall determine the theoretical yield of Fe₂O₃. This can be obtained as follow:

From the balanced equation above,

11 moles of O₂ reacted to produce 2 moles of Fe₂O₃.

Therefore, 7.55 moles of O₂ will react to produce = (7.55 × 2)/11 = 1.37 moles of Fe₂O₃.

Thus, the theoretical yield of Fe₂O₃ is 1.37 moles.

Finally, we shall determine the percentage yield. This can be obtained as follow:

Actual yield of Fe₂O₃ = 2 moles

Theoretical yield of Fe₂O₃ = 1.37 moles

Percentage yield =?

Percentage yield = Actual yield /Theoretical yield × 100

Percentage yield = 2 / 1.37 ×100

Percentage yield = 200 / 1.37

Percentage yield = 145.99%

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

according to the u.s. department of agriculture, the label of "certified organic" comes with a set of highly regulated standards for environmental stewardship and resource conservation. some of these include maintenance and improvement of soil quality, prevention of ground and surface water contamination, greenhouse gas regulation, encouragement of biodiversity and conservation of water and energy (see references 1). organic practices integrate natural methods such as mulching, plant diversity, native and adapted plants, crop rotation and the introduction of beneficial insects to control pests without synthetic pesticides.

environmental implications of pesticides

synthetic pesticides ensure high crop yields. while effective in achieving this goal, pesticides contaminate soil, air, ground and surface water, as well as the plants and animals that come into contact with these contaminated sources. freshwater and marine organisms are particularly susceptible to pesticides through agricultural runoff. pesticides also reduce soil fertility (necessitating the use of synthetic fertilizers) and can travel far from the original source, contaminating water and air hundreds of miles from the location of application (see references 2).

health implications of organics

although a subject of particular debate, many recent findings show that organic food is healthier than conventionally grown food. according to the usda, an extensive european union-funded study found that organically grown foods contain more beneficial compounds, such as the vitamins and antioxidants needed to combat many diseases (see references 5). organic milk, meat and eggs are regulated to ensure they are free of hormones administered to conventional livestock and poultry.

health implications of pesticides

pesticides affect human health in three ways: through skin contact, inhalation and ingestion. acute and long-term exposure to pesticides can cause serious health problems for farmers who apply them. the majority of other people are affected by drinking contaminated water and eating contaminated marine life (see references 3). pesticides have been linked to neurological disorders, endocrine and reproductive disorders, immune system deficiencies and cancer. according to the world health organization, acute pesticide poisoning (app) is responsible for significant annual mortality, especially in developing nations (see references 4).

other important considerations

not every small farm or business owner can afford the costly certification process required to be considered "certified organic," even if the farm is not using chemicals. "transitional" farms include those that once used chemicals and are now transitioning to organic-only production. in addition, though organic farming methods offer obvious environmental benefit, an organic apple shipped from around the world creates a different set of environmental problems. locally grown food (particularly locally grown, organic food) is key in sustainable food production.