Explain the negative impacts of chemical fertilizers, how temporary hard water can be softened, and the definition of mechanical advantage in simple machines.

Here are the answers to question 2: a) Four reasons why farmers should be discouraged from using chemical fertilizers: • Chemical fertilizers can lead to eutrophication of water bodies, causing algal blooms and oxygen depletion, harming aquatic life. • Overuse can cause soil acidification and reduce soil fertility over time by killing beneficial microorganisms. • They can contaminate groundwater and surface water with nitrates and phosphates, posing health risks to humans and animals. • The production of chemical fertilizers is energy-intensive and contributes to greenhouse gas emissions. b) (i) Temporary hard water is water that contains dissolved calcium hydrogencarbonate (Ca(HCO_3)_2) or magnesium hydrogencarbonate (Mg(HCO_3)_2). It can be softened by boiling. (ii) Chemical equation to show how temporary hard water can be softened by heating: Ca(HCO_3)_2(aq) heat CaCO_3(s) + H_2O(l) + CO_2(g) The insoluble calcium carbonate precipitates out, removing the hardness. c) (i) A lever is a simple machine consisting of a rigid bar that pivots around a fixed point called a fulcrum, used to multiply force or change the direction of force. (ii) Explanations of terms as applied to simple machines: (α) Mechanical advantage is the ratio of the load (output force) to the effort (input force). It indicates how much a machine multiplies the applied force. (β) Velocity ratio (or ideal mechanical advantage) is the ratio of the distance moved by the effort to the distance moved by the load. It is a theoretical value that does not account for friction. d) (i) Food processing is the transformation of raw ingredients into food, or of food into other forms, for consumption. This can involve physical or chemical methods. (ii) (α) Two advantages of food processing: • It increases the shelf life of food, reducing spoilage and waste. • It makes food safer by eliminating harmful microorganisms and toxins. (β) One disadvantage of food processing: • It can lead to a loss of nutrients (e.g., vitamins, minerals) during processing. Send me the next one 📸