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3 years ago

Calculate the enthalpy of the formation of butane, C4H10, using the balanced chemical equation and the standard value below:

Chemistry

1 answer:

zavuch27 [327]3 years ago

6 0

Answer:

+125.4 KJmol-1

Explanation:

∆H C4H10(g) = -2877.6kJ/mol

∆H C(s)=-393.5kJ/mol

∆H H2(g) = -285.8

∆H reaction= ∆Hproducts - ∆H reactants

∆H reaction= (-2877.6kJ/mol) - [4(-393.5kJ/mol) +5(-285.8)]

∆H reaction= +125.4 KJmol-1

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What is the name of a solution whose concentration of solute is equal to the maximum concentration that is predicted from the so

Nat2105 [25]

Usually you would call this a saturated solution. I hope this helps.

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3 years ago

Read 2 more answers

If you have a solution that contains 46.85 g of codeine, C18H21NO3, in 125.5 g of ethanol, C2H5OH, what is the mole fraction of

irakobra [83]

Answer:

0.22

Explanation:

Given, Mass of $C_{18}H_{21}NO_3$ = 46.85 g

Molar mass of $C_{18}H_{21}NO_3$ = 299.4 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{46.85\ g}{299.4\ g/mol}$

$Moles\ of\ C_{18}H_{21}NO_3= 0.1565\ mol$

Given, Mass of $C_{2}H_{5}OH$ = 125.5 g

Molar mass of $C_{2}H_{5}OH$ = 46.07 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{125.5\ g}{46.07\ g/mol}$

$Moles\ of\ C_{2}H_{5}OH= 0.5535\ mol$

So, according to definition of mole fraction:

$Mole\ fraction\ of\ codeine=\frac {n_{codeine}}{n_{codeine}+n_{ethanol}}$

$Mole\ fraction\ of\ codeine=\frac{0.1565}{0.1565+0.5535}=0.22$

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3 years ago

3. In the picture, a girl with a weight of 540 N is balancing on

svet-max [94.6K]

Answer:

340 N

Explanation:

Force formula

The force formula is defined by Newton's second law of motion: Force exerted by an object equals mass times acceleration of that object: F = m ⨉ a. To use this formula, you need to use SI units: Newtons for force, kilograms for mass, and meters per second squared for acceleration.

Equilibrium

It is a state of rest or balance due to the equal action of opposing forces. equal balance between any powers, influences, etc.; equality of effect. mental or emotional balance; equanimity: The pressures of the situation caused her to lose her equilibrium.

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2 years ago

2.)If a chemical reaction such as photosynthesis begins with 6 atoms of carbon (C), how many atoms of carbon (C) should be in th

12345 [234]

Answer:

3 atoms of carbon

Explanation:

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2 years ago

hi:) anyone able to explain no.2 of what happens to particles of a solid that is heated until it melts? I don’t understand it. T

Viefleur [7K]

In a solid the particles are all really close together and stuck like that. As the solid melts and becomes a liquid the particles spread out. A solid won’t easily change its shape because the particles are bound together but in a liquid the shape is more fluid, take water when you pour it into a container it will change to fit the shape of a container this is because the particles aren’t as close and can move around. The particles of a solid change when it melts because it is changing states to a liquid.

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2 years ago