Answer:
a) ΔH°rxn = -9.2kJ/mol
b) ΔH°rxn = -9.2kJ/mol
Explanation:
Using Hess's law, you can find ΔH of a reaction from ΔH of formation of the substances involved in the reaction, thus:
ΔH°rxn = ∑(BE(reactants)) − ∑(BE(products))
Or:
ΔH°rxn = ∑(nΔH°f (products)) − ∑(mΔH°f (reactants))
For the reaction:
H₂(g) + I₂(g) → 2HI(g)
a) Using the first equation:
ΔH°rxn = ΔH (H-H) + ΔH (I-I) - 2ΔHBE (H-I)
ΔH°rxn = 436.4kJ + 151kJ - 2×298.3kJ
<em>ΔH°rxn = -9.2kJ/mol</em>
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b) Using the second equation:
ΔH°rxn = 2Δ°f (HI) − ΔH°f (H₂) - ΔH°f (I₂)
ΔH°rxn = 2×25.9kJ - 0kJ - 61.0kJ
<em>ΔH°rxn = -9.2kJ/mol</em>
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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.
Answer:
172.385 g/mol
Explanation:
Magnesium Tartrate is C4H4MgO6
C - 12.01 g/mol
H - 1.01 g/mol
Mg - 24.305 g/mol
O - 16.00 g/mol
12.01(4) + 1.01(4) + 24.305 + 16(6) = 172.385 g/mol
B. carbon-13 is not an allotrope of Carbon.
Allotropes<span> are elements on the periodic table that have more than one crystalline form. </span>Isotopes<span> are atoms of the same element with the same atomic number but have a different mass number.
C-13 is an isotope of carbon, not an allotrope.</span>
Crystals of hydrated magnesium sulfate used as a purgative or for other medicinal use
It on googIe
Hope that helps