CHEM 181 Study Guide - Midterm Guide: Colony Collapse Disorder, Brazil Nut, Environmentally Friendly

• School: McGill University
• Department: Chemistry
• Course: CHEM 181
• Professor: David Harpp

Document Summary

Hunter-gatherers crops modern fertilizers (von liebig, 19th cent) modern pesticides. Farmers used to make up ~70% of the world population until 50yrs ago. 2n + 3h2 2nh3: ammonia can be pumped directly into soil, but usually: Nh3 + hno3 (nh4)(no3) ammonium nitrate. Nh4no3 issues: used in explosives slowly decompose to n2o, laughing gas/greenhouse gas like co2. Hydroponics, early 20th cent: gericke: introduced soilless gardening (hydroponics) @greenhouses, use ground coconut shells, etc as planting material, then add nutrients, no insects bc enclosed environment, this method is used on cucumbers, tomatoes. Insects/pests: eat our plants: fungi: cause cosmetic scars on food, ruins it, disease, weeds: competition. Apple scab: fungus, only a cosmetic issue. Black spot fungus on flowers: crop destruction. Corn borer invades and nests in corn. Need to register pesticides for specific uses lots of paperwork. Overall, humans consume ~1. 5g natural pesticides per day, 99. 99% is natural . Natural or synth, human liver/kidneys detoxes them the same way.