Answer:
Answer D. Picture II shows a chemical change, because the same substance changes form
Explanation:
This is the temperature that water molecules slow down enough to stick to each other and form a solid crystal
The percent yield of the reaction : 89.14%
<h3>Further explanation</h3>
Reaction of Ammonia and Oxygen in a lab :
<em>4 NH₃ (g) + 5 O₂ (g) ⇒ 4 NO(g)+ 6 H₂O(g)</em>
mass NH₃ = 80 g
mol NH₃ (MW=17 g/mol):
![\dfrac{80}{17}=4.706](https://tex.z-dn.net/?f=%5Cdfrac%7B80%7D%7B17%7D%3D4.706)
mass O₂ = 120 g
mol O₂(MW=32 g/mol) :
![\tt \dfrac{120}{32}=3.75](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B120%7D%7B32%7D%3D3.75)
Mol ratio of reactants(to find limiting reatants) :
![\tt \dfrac{4.706}{4}\div \dfrac{3.75}{5}=1.1765\div 0.75\rightarrow O_2~limiting~reactant(smaller~ratio)](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B4.706%7D%7B4%7D%5Cdiv%20%5Cdfrac%7B3.75%7D%7B5%7D%3D1.1765%5Cdiv%200.75%5Crightarrow%20O_2~limiting~reactant%28smaller~ratio%29)
mol of H₂O based on O₂ as limiting reactants :
mol H₂O :
![\tt \dfrac{6}{5}\times 3.75=4.5](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B6%7D%7B5%7D%5Ctimes%203.75%3D4.5)
mass H₂O :
4.5 x 18 g/mol = 81 g
The percent yield :
![\tt \%yield=\dfrac{actual}{theoretical}\times 100\%\\\\\%yield=\dfrac{72.2}{81}\times 100\%=89.14\%](https://tex.z-dn.net/?f=%5Ctt%20%5C%25yield%3D%5Cdfrac%7Bactual%7D%7Btheoretical%7D%5Ctimes%20100%5C%25%5C%5C%5C%5C%5C%25yield%3D%5Cdfrac%7B72.2%7D%7B81%7D%5Ctimes%20100%5C%25%3D89.14%5C%25)
3 elements are present in HCOOH - hydrogen, oxygen, and carbon.
Answer: I believe the answer would be methane
Explanation:
Hope this helps