Which one of the following statements about alkaline earth metals is NOT true ?

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Q: 9 (CAPF/2020)

Which one of the following statements about alkaline • earth metals is NOT true ?

question_subject: 

Science

question_exam: 

CAPF

stats: 

0,44,70,21,24,25,44

keywords: 

{'earth metals': [0, 0, 0, 1], 'magnesium': [1, 0, 2, 3], 'alkaline': [2, 0, 0, 2], 'element beryllium': [0, 0, 0, 1], 'barium metal': [0, 0, 0, 1], 'strontium': [0, 0, 2, 2], 'gemstone ruby': [0, 0, 0, 1], 'photosynthesis': [20, 0, 4, 11], 'red flame': [0, 0, 0, 1], 'sunlight': [0, 0, 1, 0], 'red colour': [1, 0, 4, 4], 'energy': [0, 0, 1, 2], 'chlorophyll': [5, 0, 1, 4], 'green plants': [1, 0, 0, 1]}

Option 1 states that strontium salts burn with a red flame. This is true; strontium compounds are known for producing a characteristic red color when they are burned.

Option 2 states that barium metal is used in medicine to examine the alimentary canal of a patient by X-ray. This is true; barium sulfate is often used as a contrast medium in X-ray imaging to help visualize the digestive system.

Option 3 states that green plants need magnesium in order to make chlorophyll, which traps the energy from sunlight in photosynthesis. This is true; magnesium is an essential nutrient for plants and is a central component of the chlorophyll molecule.

Option 4 states that the red color of the gemstone Ruby is due to the element beryllium present in it. This statement is NOT true. The red color of Ruby is actually due to the element chromium, not beryllium.

In conclusion, option 4 is the correct answer as it provides incorrect information about the element responsible for the red color of Ruby.