Thabelo cc (ltd), is a juice manufacturing plant situated in the eastern cape. a backward feed triple effect evaporator is fed at 5 000 kg/h with an orange juice concentrate that contains 5 mass% solids. the temperature of the feed is 27°c. the specification of the final juice concentrate is 27 mass% solids. steam is available at 265 kpa and the vapour pressure in the second effect is 13.4 kpa. additional information: a. the bpr can be estimated by: bpr(°c) = 1.65 x+5.35 x2 b. the heat transfer surfaces are the same in all three effects c. the heat capacity of the solution is 4.3 kj/kg. k and is constant over temperature and concentration ranges d. the heat of the solution is negligible e. the overall heat transfer coefficients are estimated as u1= 3.089; u2= 1.954 and u3= 1.127 kw/m2.k f. perform only one iteration g. as the feed enters as a cold stream the first effect requires more heat. normally we need to adjust the temperature at1, at2, at3 proportionately. in this case, adjust at1 by increasing the temperature by 3 k, at2 by decreasing the temperature by 1.4 k and at3 by decreasing the temperature by 2.95 k. 3.1. draw a schematic diagram to depict the evaporation process labelling all process streams and showing all information required for the system. (6) 3.2. determine the amount steam required for the process. (20) 3.3. determine the overall steam economy. (4) 3.4. determine the area of each effect.

beta decay is the answer

3

explanation:

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

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.