1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
garri49 [273]
1 year ago
11

I don’t know how to do this properly like I got an answer but I don’t know if it’s right

Chemistry
1 answer:
egoroff_w [7]1 year ago
4 0

To calculate this, we will use the chemical equations as math equations and add them.

Firtly, we want the equation for the formation of CH₃CHO(g), so this will be the only product.

The reactants must be only the elements in their standard form, so C(g), O₂(g) and H₂(g). I would be more correct to use C(s), but since we odn't have information for this, we will assume it wants with C(g).

So, the reaction we want is:

C(g)+O_2(g)+H_2(g)\to CH_3CHO(g)

To balance the reaction, we can just do for eqach element separately, maintaining the coefficient of 1 on CH₃CHO(g):

\begin{gathered} 2C(g)+\frac{1}{2}O_2(g)+2H_2(g)\to CH_3CHO\mleft(g\mright) \\ \Delta H=? \end{gathered}

Now, we want to get to this equation adding the equations we want. We will apply the same operations to the enthalpies to get the enthalpy of formation.

The first given equation has the CH₃CHO(g), but it is on the left side and with coefficient of 2, so we need to invert the reaction and divided every coefficient by 2. The same operations have to be applied to the enthalpy, so the sign of the enthalpy will invert and it will be divided by 2:

\begin{gathered} 2CO_2(g)+2H_2O(l)\to CH_3CHO(g)+\frac{5}{2}O_2(g)_{} \\ \Delta H=\frac{2308.4kJ}{2}=1154.2kJ \end{gathered}

The second given equation has both C(g) and O₂(g), but since the third equation also has O₂(g), we will look just for C(g). We need 2 C(g), so we will need to doulbe the equation and its enthalpy:

\begin{gathered} 2C(g)+2O_2(g)\to2CO_2(g) \\ \Delta H=2\cdot-414.0kJ=-828.0kJ \end{gathered}

For the last, we will look into H₂(g) and since all the equations are balanced, O₂(g) will also be balanced by the end of it.

We need 2 H₂(g), so we don't need to do anything with this reaction:

\begin{gathered} 2H_2(g)+O_2(g)\to H_2O(l) \\ \Delta H=-597.4kJ \end{gathered}

Now, we add the equations:

\begin{gathered} \cancel{2CO_2\mleft(g\mright)}+\cancel{2H_2O\mleft(l\mright)}\to CH_3CHO(g)+\cancel{\frac{5}{2}O_2(g)}_{} \\ 2C(g)+\cancel{2O_2(g)}\to\cancel{2CO_2(g)} \\ 2H_2(g)+\cancel{O_2(g)}\to\cancel{H_2O(l)} \\ ------------------------------- \\ 2C(g)+\frac{1}{2}O_2(g)+2H_2(g)\to CH_3CHO(g) \end{gathered}

And we do the same with the enthalpies:

\begin{gathered} \Delta H=1154.2kJ+(-828.0kJ)+(-597.4kJ) \\ \Delta H=1154.2kJ-828.0kJ-597.4kJ \\ \Delta H=-271.2kJ \end{gathered}

This is the enthalpy for this reaction. To get the molar enthalpy of formation, we need to divide this value by the coefficient of CH₃CHO(g). Since this coefficient is 1, we have:

\Delta H_m=-\frac{271.2kJ}{1mol}=-271.2kJ\/mol

So, the molar enthalpy of formation given the data is -271.2 kJ/mol.

You might be interested in
1 point
I am Lyosha [343]

65.47 \: g \times  \frac{12 \: donuts}{25.64 \: g} = 30.64118565

i \: have \: 31 \: donuts

8 0
2 years ago
Read 2 more answers
A 0.3146 g sample of a mixture of NaCl ( s ) and KBr ( s ) was dissolved in water. The resulting solution required 45.70 mL of 0
Masteriza [31]

Answer:

The answer to the question is

The mass percentage of NaCl(s) in the mixture is 49.7%

Explanation:

The given variables are

mass of sample of mixture = 0.3146 g

Volume of AgNO₃ required to react comletely with the chloride ions = 45.70 mL

Concentration of the AgNO₃ added = 0.08765 M

The equations for the reactions oare

NaCl(aq) + AgNO₃ (aq) = AgCl(s) + NaNO₃(aq)

AgNO₃ (aq) + KBr (aq) → AgBr (s) + KNO₃

The equation for the reaction shows one mole of NaCl reacts with one mole of AgNO₃ to form one mole of AgCl

Thus 45.70 mL of 0.08765 M solution of AgNO₃ contains\frac{45.7}{1000} (0.08765) = 0.004 moles

Therefore the sum of the number of moles of Br⁻ and Cl⁻

precipitated out of the solution =  0.004 moles

Thus if the mass of NaCl in the sample = z then the mass of KBr = y

However the mass of the sample is given as 0.3146 g which  means the molarity of the solution is 0.004 moles

given by

\frac{z}{58.44} + \frac{y}{119} = 0.004 moles  and z + y = 0.3146

Therefore z = 0.3146 - y which gives

\frac{(0.3146-y)}{58.44} + \frac{y}{119} = 0.004 moles

-8.7×10⁻³y +0.54×10⁻³ = 0.004

or 8.7×10⁻³y = 1.37769× 10⁻³

y = 0.158 g and z = 0.156 Thus the mass of NaCl = 0.156 g and the mass percentage = 0.156/0.3146×100 = 49.7% NaCl

The mass percentage of NaCl(s) in the mixture is 49.7%

8 0
3 years ago
If you have a balloon inside a car at noon during a hot summer day, the balloon molecules
aleksandrvk [35]

Answer:

it decreases

Explanation:

because its false

6 0
3 years ago
Read 2 more answers
4. Which statement is true?
worty [1.4K]

Answer:

give a picture

Explanation:

4 0
2 years ago
What happens when stress builds at faults? Select three options
Stels [109]

Answer:

When Stress builds up at faults, the 3 options that are correct and can happen

- Rock can bend and break;

- Earthquakes develop at Earth's surface

- Forces affect Earth's rocks

Explanation:

This is a Geography question

- Rock can bend and break

When Stress builds up at faults, it leads to a geologic activity that causes a lot of pressure that lead to the movement of the earth's crust. The movement creates such intense pressure on the rocks, that, with time, they twist, bend, and break due to this pressure.

- Earthquakes develop at Earth's surface

As explained earlier, this intense pressure can lead to rocks breaking, as these rocks break inside the earth's crust, the gaps that come into play after the breaking of the rocks causes the remaining rocks to adjust, releasing a lot of force, and subsequently creating earthquakes.

- Forces affect Earth's rocks

As explained earlier, the forces resulting from these intense pressures, affect the earth's rocks. They move them both vertically and horizontally, change their shape and eventually break them.

Hope this Helps!!!

8 0
3 years ago
Other questions:
  • Given the following formula 2 KCIO3 -> 2 KCI + 3 O2 how many moles of O2 can be produced by letting 12 moles of KCIO3 react?
    5·1 answer
  • What is the mass number of beryllium with 5 neutrons
    7·1 answer
  • An element is matter that is composed of one type of (atom/quark). 8. the unit of measurement used for atomic particles is the (
    15·1 answer
  • The value for Kw is 1.0 x 10-14 at 298K, but this value is temperature dependent. Given what you know about Kw and acid/base che
    15·1 answer
  • A sample of helium has a volume of 325 mL and a pressure of 655 mmHg. What will be the pressure, in mmHg, if the sample of heliu
    11·1 answer
  • What happens if you mix Hydrochloric Acid (HCl) and Sodium Bicarbonate (NaHCO3 ) together?
    8·2 answers
  • Van der Waals forces hold molecules together by: A. moving electrons from one molecule to another. B. attracting a lone pair of
    10·1 answer
  • Help would be much appreciated! i'll mark brainliest
    12·1 answer
  • What variables affect mass? (include observations)​
    11·1 answer
  • Why it is important for humans to conserve freshwater?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!