Because your Teeth are composed of calcium, phosphorus, and other minerals. ... But bones are still not as strong as teeth. The hardest part of the human body ,teeth mostly consist of a calcified tissue called dentine. The tooth's dentine tissue is covered in enamel, that hard, shiny layer that you brush.
The mass of nucleons (and thus of the nucleus) is roughly 1000 times greater than that of electrons.
Answer:
NH3
Explanation:
2NH3(aq)+CO2(aq)→CH4N2O(aq)+H2O(l)
So for two moles of NH3 we need one mole of CO2. So let's count moles for each reagent.
n(NH3)=m(NH3)/M(NH3)=135700/17,03=7968.29 mol
n(CO2)=m(CO2)/M(CO2)=211400/44.01=4803.45 mol
From equation we have to divide n(NH3) by 2 because we need two equivalent per one CO2. That will be 3984.145. So the limiting agent is NH3 because it's not enough of it to react with all CO2
It takes 33.4 s for the concentration of A to fall to one-fourth of its original value.
A <em>half-life</em> is the time it takes for the concentration to fall to half its original value.
Assume the initial concentration is 1.00 mol/L. Then,

The concentration drops to one-fourth of its initial value in two half-lives.
∴ Time = 2 × 16.7 s = 33.4 s