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Describe a laboratory or field method to show any two of the following: (a) The percentage germination of a cereal - Leaving Cert Agricultural Science - Question 4 - 2009
Question 4
Describe a laboratory or field method to show any two of the following: (a) The percentage germination of a cereal. (b) The calorific value of a farm animal ration... show full transcript
Worked Solution & Example Answer:Describe a laboratory or field method to show any two of the following: (a) The percentage germination of a cereal - Leaving Cert Agricultural Science - Question 4 - 2009
Step 1
(a) The percentage germination of a cereal.
Answer
To determine the percentage germination of a cereal, we can use the following method:
- Prepare the Seed Tray: Use a seed tray or seed module filled with a suitable growing medium. Add 100 seeds (or a known quantity).
- Environmental Conditions: Keep the tray warm and damp, ensuring it receives enough light for the seeds to germinate. Leave the seeds undisturbed for approximately two weeks.
- Counting Germinations: After the germination period, count the number of seeds that have sprouted. This should be done carefully to avoid damaging the seedlings.
- Calculating Percentage: Calculate the germination percentage using the formula: ext{Percentage Germination} = rac{ ext{Number of Seeds Germinated}}{ ext{Total Seeds Sown}} imes 100
Step 2
(b) The calorific value of a farm animal ration.
Answer
To measure the calorific value of a farm animal ration, follow these steps:
- Preparation: Get a known mass of the animal ration and weigh it accurately.
- Set Up the Apparatus: Place the sample in a calorimeter (if available), or burn it in a controlled environment, like a bomb calorimeter.
- Heating Water: Fill a known volume of water in a suitable container and record its temperature.
- Igniting the Sample: Ignite the animal ration sample and allow it to burn completely, heating the water in the container.
- Temperature Change: After combustion, measure the final temperature of the water.
- Calculating the Calorific Value: Use the formula: ext{Calorific Value} = rac{( ext{mass of water} imes 4180 imes ext{change in temperature})}{ ext{mass of sample}}