Eggshells have a similar chemical composition to our tooth enamel, making them react similarly with other chemicals. This can help us understand what stains tooth enamel. When we brush an eggshell with fluoridated toothpaste, it strengthens the shell and protects it from acid, just like it does for our tooth enamel.
Because they share a similar composition, similar chemicals affect their structures in positive or negative ways. For example, fluoride – a staple in many dental practices – strengthens both enamel and eggshells and helps protect them from acids. Acids weaken and break down both substances. Scientists find this particularly concerning given that the ocean is growing increasingly acidic. They fear this may weaken the eggs of some marine species and harm their chance of survival. Most dentists recommend limiting aggressively acidic foods and beverages such as soft drinks.
Explanation : We have Ce-141 half life given as 32.5 days so if the activity is 3.8 </span><span>μci after 162.5 days of time elapsed we have to find the initial activity.
We can use this formula;
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3.8 / = ((0.693 X 162.5 ) / 32.5) = 121.5 <span> On solving we get, The initial activity as 121.5 </span>μci
= 
((0.693 X 162.5 ) / 32.5) = 121.5