Even though two grams seemed to disappear or vanish, the law of conversation of mass still holding true. Mercuric oxide, when heated, forms a gas of mercury and oxygen. During the investigation, some gas could have escaped or evaporated.
<span>decomposition of SrCO3 to SrO and CO2 =change in mass
moles of CO2 =(1.850 g - 1.445 g).
</span>Mass of <span>C<span>O2</span></span><span> in mixture: 1.850-1.445 = 0.405g
</span>0.405g/44.01 g/mol <span>C<span>O2</span></span><span> = 0.0092 moles </span><span>C<span>O2</span></span><span>.
</span>ratio of <span>C<span>O2</span></span><span> to SrO in Sr</span><span>C<span>O3</span></span><span> is 1:1
</span><span> mass ratio = 1.358/1.850 = 0.7341, </span>
or 73.41% Sr<span>C<span>O3</span></span><span>.
</span>hope this helps
P (Phosphorus) has an atomic number of 15. Therefore, it has 15 protons. A charge of -3 indicates that it has gained 3 electrons. Therefore, it has 18 electrons. Hope this helps :)
Answer:
New experimental methods
Technological inventions
Explanation:
A scientific theory is usually not based on speculation. Scientific theories must have a solid empirical basis.
However, experimental methods are limited to the caliber of equipments available at the time in which a theory is formulated. With advancing years, more technological sophistication leads to the invention of new instruments and ultimately, the development of new experimental methods.
These innovations are likely to alter existing scientific theories as new evidences emerge, hence the answer.
