Answer:
ΔH rxn = -1010 kJ/molC₂H₂
Explanation:
To obtain the enthalpy change for a reaction from bond energies what we do is to make an inventory of the bonds broken and formed for the balanced chemical reaction:
C₂H₂ + 5/2O₂ ⇒ 2CO₂ + H₂O
Bond Broken Bonds Formed
2 C-H + 1 C≡C + 5/2 O=O 4C=O + 2 H-O
Enthalpy bonds broken:
2 mol (456 kJ/mol)+ 1 mol (962 kJ/mol) + 5/2 mol (499 kJ/mol) = 3121.5 kJ
Enthalpy bond formed:
4 mol (802 kJ/mol) + 2 mol (462 kJ/mol) = 4132.0 kJ
ΔH rxn = H broken - H formed = 3121.5 kJ - 4132.0 kJ = - 1010 kJ (per mol C₂H₂ )
The answer is relative dating, btw
Answer:
B
Explanation:
Assuming the units are all supposed to be the same
A cube shaped cell with a 1 um³ volume would have a dimensions of 1 x 1 x 1 (because volume = length x width x height and 1 x 1 x 1 =1)
If we double the dimensions, we have a cube with the dimensions 2 x 2 x 2.
The surface area of each face of the cube is the length x width, so 2 x 2. This means the surface area of each face of the cube is 4 um².
There are 6 faces of a cube, so the total surface area is 6 x 4 um² = 24 um².
Swallow hole is also known as a sinkhole refers to a hole or depression in the ground resulted due to certain kind of collapse of the surface layer. The majority of them are the result of karst procedures, like the suffosion processes or the chemical dissolution of the carbonate rocks.
The sinkholes differ in size from 1 to 600 meters, both in depth and diameter, and differ in form from soil-lined bowls to bedrock-edged chasms. The sinkhole may get produced suddenly or slowly, and are observed all through the globe.
Answer:
"HEMOGLOBINA. Las características de la hemoglobina (Hb) como amortiguador están íntimamente vinculadas a la capacidad de disociación del grupo imidazólico del aminoácido histidina unido al hierro que contiene el grupo hemo (ver figura inferior)."
Link: http://www.ehu.eus/biomoleculas/buffers/buffer4.htm#:~:text=HEMOGLOBINA&text=Las%20caracter%C3%ADsticas%20de%20la%20hemoglobina,hemo%20(ver%20figura%20inferior).
