Topic content:
Among the following statements about common sense of life, the correct one is
A. Turn on the exhaust fan immediately when you find gas leakage at home
B. Wash clothes with hard water
C. Burning crop straw after busy farming
D. Implement classified waste recycling
Best answer:
D
Answer analysis:
A、 The gas is combustible, and the exhaust fan cannot be opened in case of leakage, so A is wrong;
B、 The soluble calcium magnesium compounds contained in hard water can combine with soap to produce precipitation, which wastes soap, so B is wrong;
C、 Straw burning is not conducive to environmental protection, so C is wrong;
D、 The classified recycling of garbage is conducive to protecting the environment and saving resources. The practice is correct, so D is correct;
Therefore, D
Test core:
The existence form of elements in human body:
① Carbon, hydrogen, oxygen and nitrogen mainly exist in the form of water, sugar, protein, vitamins and fat.
② Other elements mainly exist in aqueous solution in the form of inorganic salts.
③ Calcium element mainly exists in the form of hydroxycalcium phosphate [Ca10 (PO4) 6 (OH) 2] crystal.