What acid rain does, and how scrubbers help
Acid rain harms plants: the gases SO₂ and NO₂ enter through the stomata and harm the cells of the leaf; chlorophyll breaks down and the stomata are blocked or misshapen, so less CO₂ is absorbed and less glucose is made. Acid rain also washes (leaches) calcium and magnesium out of the soil, which then loses fertility. It attacks limestone (calcium carbonate) in buildings and monuments: H₂SO₄ + CaCO₃ → CaSO₄ + CO₂ + H₂O. Forests, water and wild plants become less productive, biodiversity falls, and air and water quality fall, with costs for health and the economy. Science and technology help. Scrubbers in factory and power-station chimneys remove sulphur and nitrogen oxides before they leave. Scrubbers remove SO₂ and nitrogen oxides, not CO₂. Clean energy (solar, wind, hydropower) makes none of these oxides. Acid rain is not caused by CO₂ alone, since normal rain is already slightly acidic, and it does not burn skin.
Chalk or eggshell in vinegar, with a grown-up who handles the vinegar. Put a piece of chalk or eggshell in a cup of vinegar and another in a cup of water. Watch from a distance for a few minutes. Do not taste or sniff. Describe what changes, and say what this tells you about acid and calcium carbonate. Then draw a paper model of a scrubber: a chimney with a filter box that holds back the oxides. No smoke, gas or water spray.