Answer: D.
Explanation: Females have XX chromosomes while males have XY
Answer : The enthalpy change for the reaction is 1043 kJ/mol.
Explanation :
The given chemical reaction is:

As we know that:
The enthalpy change of reaction = E(bonds broken) - E(bonds formed)
![\Delta H=[(2\times B.E_{C\equiv O})+(1\times B.E_{O\equiv O})]-[2\times B.E_{C=O}]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%282%5Ctimes%20B.E_%7BC%5Cequiv%20O%7D%29%2B%281%5Ctimes%20B.E_%7BO%5Cequiv%20O%7D%29%5D-%5B2%5Ctimes%20B.E_%7BC%3DO%7D%5D)
Given:
= 1074 kJ/mol
= 499 kJ/mol
= 802 kJ/mol
Now put all the given values in the above expression, we get:
![\Delta H=[(2\times 1074kJ/mol)+(1\times 499kJ/mol)]-[2\times 802kJ/mol]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%282%5Ctimes%201074kJ%2Fmol%29%2B%281%5Ctimes%20499kJ%2Fmol%29%5D-%5B2%5Ctimes%20802kJ%2Fmol%5D)

Therefore, the enthalpy change for the reaction is 1043 kJ/mol.
Hello!
Antifreeze says it in the name. This means that it helps prevent freezing. The liquid that would freeze if you wouldnt use the antifreeze is water. This means that the antifreeze has to have a higher freezing point then water, because otherwise it would only freeze faster!
Hope this helped you!
PH (potential of hydrogen) is a numeric scale that is used to show the acidity or basicity of an aqueous solution. It tells how acidic or alkaline a substance is . The pH values ranges from 0 to 14, such that acidic solutions have values between 1 to 6.9 with most acidic having a pH value of 1 and those that are basic have values from 7.1 to 14, with most acidic having a value of 14. Acidic compounds contain replaceable hydrogen ions while basic compounds contain hrdroxyl ions. In this case, a coke has a pH of 3.5 (acidic) which means that it has an excess of hydrogen ions (H+) and would be called an acid.