Q21. Describe how each step of the scientific method can be applied to investigate and solve the problem of a plant's leaves turning yellow. Q22. How does temperature affect the way water behaves, like turning into ice or steam? Share an example of how you have observed these changes in your everyday life.
Answer (1)
Q21: To investigate and solve the problem of a plant's leaves turning yellow using the scientific method, follow these steps:
Observation: Notice that the plant's leaves are turning yellow. This is your starting point in identifying that there is a problem with the plant.
Question: Ask why the leaves are turning yellow. Is it due to lack of nutrients, improper watering, disease, or some other factor?
Hypothesis: Formulate a hypothesis, or educated guess, about what might be causing the leaves to turn yellow. For example, you might hypothesize that the leaves are yellow because of a nitrogen deficiency.
Experiment: Test the hypothesis. You could apply a nitrogen-rich fertilizer to the soil and observe any changes in the leaf color over a set period. Alternatively, try adjusting watering methods to see if that improves leaf color.
Data Collection: Record the observations from your experiment. Take notes on how the plant responds to changes in fertilizer and water conditions.
Analysis: Analyze the results. Did the leaves return to a healthy green color, or is there no change? Use the data collected to see if your hypothesis was correct.
Conclusion: Draw a conclusion. If the leaves turn green, then the hypothesis that a nitrogen deficiency was causing yellowing is supported. If not, consider other hypotheses or experimental setups to test further.
Report: Share your findings. This could be through a written report or discussion with others interested in plant care.
Q22: Temperature affects how water behaves by changing its state between solid, liquid, and gas. Here's how:
Freezing: Water turns into ice when its temperature drops below 0°C (32°F). This is the freezing point where liquid water becomes solid.
Boiling: Water turns into steam (gas) when heated to its boiling point, 100°C (212°F) at sea level.
An example from everyday life is boiling water on the stove. When water in a pot is heated, you will notice bubbles forming as it reaches boiling point; this is water turning into steam. Conversely, if you leave a bottle of water in the freezer, it will solidify into ice once it loses enough heat and reaches 0°C or below. These are direct observations of how temperature changes can alter the state of water.
