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4 years ago

In an endothermic reaction what is true of the enthalpy

Chemistry

1 answer:

charle [14.2K]4 years ago

4 0

Answer is: a) is has increased.

There are two types of reaction:

1) endothermic reaction (chemical reaction that absorbs more energy than it releases).

For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.

2) exothermic reaction (chemical reaction that releases more energy than it absorbs).

For example, ΔH(reaction) = -225 kJ/mol; this is exothermic reaction.

You might be interested in

Ethanol is added to gasoline because the oxygen it contains improves gasoline's burning efficiency. Its combustion reaction is g

Angelina_Jolie [31]

Answer:

A) Exothermic

B) (1) -410.5 kJ (2) -98.1 kcal

C) -976.44 kJ

Explanation:

A) By the value of ΔH (-1236 kJ), we can see that it's negative, it means that the heat is being lost by the reaction, and, because of that, the reaction is exothermic.

B) The molar mass of ethanol is 46.07 g/mol, so, at 15.3 grams, the number of moles is:

n = mass/molar mass

n = 15.3/46.07

n = 0.3321 mol

By the equation

1 mol of ethanol ----------------------- -1236 kJ

0.3321 mol of ethanol ----------------------- x

By a simple direct three rule:

x = -410.5 kJ

1 kJ --------------- 0.2390 kcal

-410 kJ ---------- y

y = -98.10 kcal

C) The molar mass of water is 18 g/mol, so the number of moles at 42.7 g is:

n = 42.7/18

n = 2.37 moles

By the equation

3 moles of water ----------------------- -1236 kJ

2.37 moles of water --------------------- x

By a simple direct three rule:

3x = -2929.32

x = -976.44 kJ

5 0

3 years ago

____________ is a point source of water pollution; _____________ is a nonpoint source of water pollution.

Deffense [45]

Answer:

good afternoon

Explanation:

thanks I will send

6 0

2 years ago

The Density of pure carbon in Diamond form is 3.52 g/cm^3. How many cubic inches would 23.7 moles of pure diamond occupy?

Vedmedyk [2.9K]

Answer : The volume of pure diamond is $0.493inch^3$

Explanation : Given,

Density of pure carbon in diamond = $3.52g/cm^3$

Moles of pure diamond = 23.7 moles

Molar mass of carbon = 12 g/mol

First we have to calculate the mass of carbon or pure diamond.

$\text{ Mass of carbon}=\text{ Moles of carbon}\times \text{ Molar mass of carbon}$

Molar mass of carbon = 12 g/mol

$\text{ Mass of carbon}=(23.7moles)\times (12g/mole)=284.4g$

Now we have to calculate the volume of carbon or pure diamond.

Formula used:

$Density=\frac{Mass}{Volume}$

Now putting all the given values in this formula, we get:

$3.52g/cm^3=\frac{284.4g}{Volume}$

Volume = $80.8cm^3$

As we know that:

$1cm^3=0.061inch^3$

So,

Volume = $0.061\times 80.8inch^3$

Volume = $0.493inch^3$

Therefore, the volume of pure diamond is $0.493inch^3$

5 0

3 years ago

According to reference table adv-10, which is the strongest reducing agent?

Mumz [18]

Li(s) (answer A)
Li is strongest reducing agent because of the lowest standard reduction potential. when something is oxidized, it reduces another substance, becoming a reducing.Hence Lithium is strongest reducing agent. Reducing agent is stronger when it has a more positive oxidation potential.

3 0

3 years ago

What is difference between ∆H and ∆H°

Elena-2011 [213]

If it is shown as ∆H , then it means that a specific chemical reaction is undergoing heat in Kelvin(K). If it is shown as ∆H° , then it means that a specific chemical reaction is undergoing heat in Celsius(C⁰).

Hope this is the answer you are looking for mate!

If it is correct then please mark my answer as the brailiest! :)

5 0

3 years ago