The dark brown color of a penny is most likely oxidation, which occurs when the copper in the penny comes in contact with oxygen.<span> </span>
<u>Answer:</u>
<em>
heat is released by the combustion of 
of methane</em>
<u>Explanation:</u>
The value of enthalpy determines whether the reaction is exothermic or endothermic. If the enthalpy change is positive, then the reaction is endothermic (heat or energy released) and if the enthalpy change is negative then the reaction is exothermic (heat or energy absorbed).
![\Delta H \ reaction=[ 2(\Delta HfCO_2)+ 4(\Delta HfH_2O)]-[2(\Delta HfCH_4)+4(\Delta HfO_2)]](https://tex.z-dn.net/?f=%5CDelta%20H%20%5C%20reaction%3D%5B%202%28%5CDelta%20HfCO_2%29%2B%204%28%5CDelta%20HfH_2O%29%5D-%5B2%28%5CDelta%20HfCH_4%29%2B4%28%5CDelta%20HfO_2%29%5D)
=![2 ( -(393.5 KJ)/mol)-[2( -74.6 KJ/mol)+4(-241.82 KJ/mol)]](https://tex.z-dn.net/?f=2%20%28%20-%28393.5%20KJ%29%2Fmol%29-%5B2%28%20-74.6%20KJ%2Fmol%29%2B4%28-241.82%20KJ%2Fmol%29%5D)
![= -787 KJ/mol-[ -149.2 KJ/mol-967.28 KJ/mol]](https://tex.z-dn.net/?f=%3D%20-787%20KJ%2Fmol-%5B%20-149.2%20KJ%2Fmol-967.28%20KJ%2Fmol%5D)
<em>In this question, </em><em>the enthalpy of formation</em><em> has positive value and hence the </em><em>reaction is endothermic</em><em> in which the heat is released.
</em>
Yes, he does have family history of heart disease.
Answer:
The answer is pp
Explanation:
Steve and Sonya's son genotype is pp. Because an inheritance of autosomal recessive disorder is with recessive allele responsible for the exceptional phenotype. In this case, Steve and Sonya are both heterozygotes, Pp, which means they both have a p allele because each one gave the boy a p, contributing to affect his son. And since we are talking about inheritance of an autosomal disorder, we know that the parents phenotypic proportions are the same.
Well one thing u could do is to reduce the amount of fossil fuels burning (idk how, maybe finding a better alternative to burning them) another way would be planting more trees, or buy energy efficient products. Basically these things just reduce the carbon footprint by reducing the amount of fossil fuels (because we only have a limited amount) i hope this helped
