Well first we can say that B. and D. are out BC they are physical changes we are looking for chemical changes when burning gas, the gas is burning and converting into heat energy AKA FIRE!!!. so the answer is indeed (A. <span>Chemical bonds are broken and others are formed.)
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<span />BTW im not a girl every one ask that. the girls in the pic is my GF
any ways i hope you can learn something new from this. :) <3 have any amazing day
Answer:
1) Hydrolysis
2)Dehydration
3)Dehydration
4)Hydrolysis
Explanation:
Hydrolysis is the chemical breakdown of substances by water and depends on the chemistry, solubility, pH, and the oxidation–reduction (Eh or redox) potential of compound
<em>https://www.sciencedirect.com/topics/earth-and-planetary-sciences/hydrolysis</em>
With hydrolysis water will be a reactant, not a product, and is associated with breaking down substances. Hence 1 and 4 being a Hydrolysis reaction.
Dehydration on the other hand, is defined as :
In a dehydration reaction, either a hydroxyl group from one molecule combines with a hydrogen atom from the other molecule, or two hydrogen atoms from one molecule combine with an oxygen atom on the other molecule. In either case, water is released, and the two molecules are joined together.
https://www.albert.io/blog/dehydration-synthesis-ap-biology-crash-course/
Therefore it is associated with creating a bond of sorts, and water is a product, which is why 2 and 3 are dehydration.
Hope this helps!
Answer:
-800 kJ/mol
Explanation:
To solve the problem, we have to express the enthalpy of combustion (ΔHc) in kJ per mole (kJ/mol).
First, we have to calculate the moles of methane (CH₄) there are in 2.50 g of substance. For this, we divide the mass into the molecular weight Mw) of CH₄:
Mw(CH₄) = 12 g/mol C + (1 g/mol H x 4) = 16 g/mol
moles CH₄ = mass CH₄/Mw(CH₄)= 2.50 g/(16 g/mol) = 0.15625 mol CH₄
Now, we divide the heat released into the moles of CH₄ to obtain the enthalpy per mole of CH₄:
ΔHc = heat/mol CH₄ = 125 kJ/(0.15625 mol) = 800 kJ/mol
Therefore, the enthalpy of combustion of methane is -800 kJ/mol (the minus sign indicated that the heat is released).
<span>[H3O+] = 10^(-pH) = 10^(-4.20) = 6.3 x 10^-5 M
pOH = 14 - pH = 14 - 4.20 = 9.80
[OH-] = 10^(-pOH) = 10^(-9.80) = 1.6 x 10^-10 M
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