Topic content:
It is found through research that aluminum can damage human brain cells, resulting in blockage of the nervous transmission system and senile dementia. Therefore, the World Health Organization stipulates that the monthly intake of aluminum should be controlled below 0.004g. Fried dough sticks are one of the common foods in northern China, and 100g oil treaty contains 0.33g alum [KAl (SO4) 2? 12H2O]. Q:
(1) The relative molecular weight of alum is
______;
(2) If the consumption of 100g fried dough sticks per day is calculated, does the intake of aluminum exceed the safe intake
(3) In daily life, besides eating less fried dough sticks, what else should we pay attention to?
Best answer:
(1) The chemical formula of alum is KAl (SO4) 2? 12H2O, relative molecular weight 39+27+32 × 2+16 × 20+1 × 24=474
(2) 0.33g × 27474=0.019g, 0.019g>0.004g, exceeding the safe intake
(3) There are many ways to absorb aluminum in life, such as using aluminum cookware, using aluminum food packaging, eating aluminum containing food, etc
So the answer is:
(1)474;
(2) Exceeded the safe intake;
(3) Try to use less aluminum pan to cook food and water (other reasonable answers are acceptable)
Answer analysis:
twenty-seven thousand four hundred and seventy-four
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.