Answer : The concentration of A after 80 min is, 0.100 M
Explanation :
Half-life = 20 min
First we have to calculate the rate constant, we use the formula :



Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = time passed by the sample = 80 min
a = initial amount of the reactant = 1.6 M
a - x = amount left after decay process = ?
Now put all the given values in above equation, we get


Therefore, the concentration of A after 80 min is, 0.100 M
You’ve not put anything below so I’m not sure what the options are but the relative charge of a proton is +1
Acid palmitic acid has higher melting point, because it has two more methylene groups.

Acid palmitic acid has higher melting point, because it has two more methylene groups.
Giving it a greater surface area and therefore more intermolecular van der waals interact than the myristic acid.
stearic arid 
linoleic acid
(two double bond)
Stearic acid has higher Melting point, because it does not have any Carbon-Carbon double bonds, whereas linoleic acid has two cis double bonds which prevent the molecules from packing closely together.
Oleic Acid and Linoleic acid.
-one double bond (cis)
Acid palmitic acid has higher melting point, because it has two more methylene groups.
For more such question on methylene group.
brainly.com/question/4279223
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Answer:
The answer to your question is ΔH° rxn = -1343.9 kJ/mol
Explanation:
P₄O₆ (s) + 2 O₂ (g) ⇒ P₄O₁₀
ΔH°rxn = ?
Formula
ΔH°rxn = ∑H° products - ∑H° reactants
H° P₄O₆ = -1640.1 kJ/mol
H° O₂ = 0 kJ/mol
H° P₄O₁₀ = -2984 kJ/mol
-Substitution
ΔH° rxn = (-2984) - (-1640.1) - (0)
-Simplification
ΔH° rxn = -2984 + 1640.1
ΔH° rxn = -1343.9 kJ/mol