# What is the rate constant for decay of the pesticide?

You are a farmer and are responsible for spraying your field with a pesticide to ensure your crops s Show more You are a farmer and are responsible for spraying your field with a pesticide to ensure your crops stay healthy. Being a green farmer you use a biodegradable pesticide that decays at a rate proportional to the amount of pesticide with a half-life of 7 days. Additionally the pesticide applied to your crops has a certain outflow into the soil and conversely the pesticide in the soil has a certain uptake into the crops. The flow of pesticide is proportional to the amount of pesticide in each area. The rate constant for the flow of pesticide from the crops to the soil is 0.5 day -1 and the rate constant for flow from the soil to the crops is 0.1 day -1 . a. What is the rate constant for decay of the pesticide? b. Write the coupled differential equations that describe the amount of pesticide in the soil and in the crops. c. The pesticide is only effective when there is more than 3000 kg in the soil. If you initially spray the crops with 10000 kg of pesticide how long until you must respray your field to ensure the pesticide is still effective? Show less