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
Slav-nsk [51]
3 years ago
7

Using table 9.4, calculate an approximate enthalpy (in kj) for the reaction of 1.02 g gaseous methanol (ch3oh) in excess molecul

ar oxygen to form gaseous carbon dioxide and gaseous water. (hint, remember to first write the balanced equation.)
Chemistry
1 answer:
Tanya [424]3 years ago
6 0

<u>Given:</u>

Mass of methanol = 1.02 g

<u>To determine:</u>

Enthalpy for the reaction of 1.02 g of methanol with excess O2

<u>Explanation:</u>

Balanced equation-

2CH3OH(g) + 3O2(g) → 2CO2(g) + 4H2O(g)

The reaction enthalpy is given as:

ΔHrxn = ∑nH°f(products) - ∑nH°f(reactants)

where n = number of moles

H°f = standard enthalpy of formation.

ΔHrxn = [2H°f(CO2(g)) + 4H°f(H2O(g))] - [2H°f(CH3OH(g)) + 3H°f(O2(g))]

           = [2(-393.5) + 4(-241.8)]-[2(-201.5) + 3(0)] = -1351.2 kJ

Now, 1 mole of CH3OH = 32 g

The calculated ΔHrxn corresponds to 2 moles of CH3OH. i.e.

The enthalpy change for 64 g of Ch3OH = -1351.2 kJ

Therefore, for 1.02g gaseous methanol we have:

ΔH = 1.02 * -1351.2/64 = -21.5 kJ

Ans: The enthalpy for the given reaction is -21.5 kJ



You might be interested in
Uniones que se dan entre atomo y moleculas
lesya [120]

Answer:

khbfd skjb skbusf szkbs

Explanation:jdfh sms kok

6 0
3 years ago
Aqueous hydrochloric acid (HCl) reacts with solid sodium hydroxide (NaOH) to produce aqueous sodium chloride (NaCl) and liquid w
Naddika [18.5K]

Answer:

87.9 % is the percent yield of H₂O

Explanation:

This is the neutralization reaction. A base reacts with an acid to produce water and the correspondly ionic salt.

NaOH  +  HCl  → NaCl +  H₂O

As we have the mass of the two reactants, we must determine the limiting reactant.

Let's convert to moles, the mass of each reactant. (mass / molar mass)

21.1 g / 36.45 g/mol = 0.579 moles of HCl

46.3 g / 40g/mol = 1.15 moles of NaOH

Ratio is 1:1, so it is obviously that the limiting reactant is the HCl. For 1.15 moles of NaOH, i need the same amount of acid, but I only have 0.579 moles

Let's work with the products now. Ratio is 1:1 again, so If I have 0.579 moles of acid, I can produce 0.579 moles of H₂O.

How many grams are 0.579 moles of water? We should find it out as this

mol . molar mass = mass → 0.579 mol . 18 g/mol = 10.4 g

We were told that the production of water was 9.17 g, so let's determine the percent yield as this:

(Yield produced / Theoretical yield) . 100 =

(9.17 g / 10.4g ) . 100 = 87.9 %

6 0
3 years ago
an unknown molecule is found to consist of 24.2% carbon by mass, 4.0% hydrogen by mass and the remaining mass is due to chlorine
Paha777 [63]

Answer:

C3 H6 Cl 3

Explanation:

C -24.2%

H -  4.0%

Cl - (100-24.2 - 4.0)=73.8 %

We can take 100g of the substance, then we have

C -24.2 g

H -  4.0 g

Cl - 73.8 g

Find the moles of these elements

C -24.2 g/12.0 g/mol =2.0 mol

H -  4.0 g/1.0 g/mol = 4. 0 mol

Cl - 73.8 g/ 35.5 g/mol = 2.1 mol

Ratio of these elements gives simplest formula of the substance

C : H : Cl = 2 : 4 : 2 = 1 : 2 : 1

CH2Cl

Molar mass (CH2Cl) = 1*12.0 +2*1.0 + 1*35.5 = 49.5 g/mol

Real molar mass = 150  g/mol

real molar mass/ Molar mass (CH2Cl) = 150 /49.5=3

So, Real formula should be C3 H6 Cl 3.

4 0
3 years ago
Read 2 more answers
__C2H4+__O2--&gt;__CO2+__H2O
mihalych1998 [28]

Answer:

Here is your answer mate :D

3 0
3 years ago
Unless otherwise instructed, you may refer to the periodic table in the Chemistry: Problems and Solutions book for this question
Tom [10]
Answer: oxygen

There is the s,p,d and f blocks, from groups 1-2 that is the s block, 13-18 that’s the p block, 3-12 is the d block and the f would be lanthanide(#57-71) and actinide (#89-103).
8 0
3 years ago
Other questions:
  • What does viscosity describe?
    7·2 answers
  • Please help, i need help! it’s for chemistry!
    11·1 answer
  • (a) 4.64 x 1024 atoms Bi into grams
    8·1 answer
  • Calculate the root mean square (rms) average speed of the atoms in a sample of xenon gas at 0.15 atm and -55c
    14·1 answer
  • If an unknown liquid has a density of 0.756 g/mL and a mass of 2.00 g, what is its volume?
    14·1 answer
  • Does the result of the calculation in question 3 justify your original assumption that all of the SCN^- is in the form of FeNCS^
    14·1 answer
  • Which of the following is the best explanation of why an ionic compound formula is a ratio of atoms
    14·1 answer
  • Lime is used in farming to reduce the acidity of the soil. The chemical name for lime is calcium oxide. When the water in the so
    14·1 answer
  • when 1 mol of glucose is burned, 2802.5kj of energy is released. calculate rhe quantity of energy released to a person by eating
    13·1 answer
  • A sample of ch4o with a mass of 32.0 g contains __________ molecules of ch4o. group of answer choices 5.32 ´ 10-23 1.00 1.88 ´ 1
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!