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
lys-0071 [83]
3 years ago
7

Is the reaction between methane and oxygen endothermic or exothermic? Explain why we burn fossil fuels, such as natural gas.

Chemistry
1 answer:
vladimir1956 [14]3 years ago
6 0
The thing that governs whether a reaction is exothermic is the energy given out / used up to break / form the bonds in the reaction. 

<span>When two substances react, the bonds in those substances first break up, releasing energy, before re-forming in a different way, taking in energy. The nature of the bonds that are broken up and reformed determines whether more energy is given out (exothermic) or taken in (endothermic)</span>
You might be interested in
Please answer fast!!! what does base stand for in science
pychu [463]
There are multiple meanings for a base. A base can be a substance that accepts hydrogen ions, or it could be something that is not acidic, in other words meaning its pH is between 7 and 14.
8 0
3 years ago
A(n) _____ is a region where fresh water and salt water mix.
Airida [17]
It is called an estuary.
7 0
3 years ago
ammonia gas reacts with oxygen gas, o2(g), to produce nitrogen dioxide and water. when 28.5 g of ammonia gas reacts with 83.4 g
jolli1 [7]

The percent yield of the reaction between ammonia gas with oxygen gas is 90.52%.

A chemical reaction between ammonia gas (NH3) with oxygen gas (O2)

NH₃ + O₂ → NO₂ + H₂O

The balanced reaction 4NH₃ + 7O₂ → 4NO₂ + 6H₂O

Calculate the number of moles from the reactant

  • Ammonia gas
    Molar mass N = 14 gr/mol
    Molar mass H = 1 gr/mol
    Molar mass NH₃ = 14 + (3 × 1) = 14 + 3 = 17 gr/mol
    mass = 28.5 grams
    n = m ÷ molar mass = 28.5 ÷ 17 = 1.68 mol
  • Oxygen gas
    Molar mass O = 16 gr/mol
    Molar mass O₂ = 16 × 2 = 32 gr/mol
    mass = 83.4 grams
    n = m ÷ molar mass = 83.4 ÷ 32 = 2.61 mol
  • n O₂ ÷ coefficient O₂ = 2.61 ÷ 7 = 0.37
    n NH₃ ÷ coefficient NH₃ = 1.68 ÷ 4 = 0.42
    0.42 > 0.37 it means that the ammonia gas is in excess and the O₂ is limiting.

According to stoichiometry, the number of moles NO₂ with the number of moles O₂ has the ratio with the coefficient in reaction.

  • Theoretically the number moles of NO₂
    n O₂ : n NO₂ = 7 : 4
    2.61 : n NO₂ = 7 : 4
    n NO₂ = 4 x 2.61 : 7 = 1.49 mol
  • The actual number of moles NO₂
    Molar mas NO₂ = 14 + (16 × 2) = 14 + 32 = 46 gr/mol
    n NO₂ = m ÷ molar mass = 61.9 ÷ 46 = 1.35 mol

The percent yield NO₂ is the ratio of the actual number of moles NO₂ with the theoretical number of moles NO₂ times 100%.

P = (1.35 ÷ 1.49) × 100%

P = 0.9052 × 100%

P = 90.52%

Learn more about stoichiometry here: brainly.com/question/13691565

#SPJ4

7 0
1 year ago
Which of the following would not be a clear indication of a chemical change
Alekssandra [29.7K]

I believe the answer is "After adding two substances together a new order is detected" because nearly all of the other answers suggest a chemical change has taken place. The reason I say "almost" is because answer two and four results in bubbles forming so the answer cannot be both. The only one to not clearly show a chemical change has occurred is the last answer.

3 0
3 years ago
All reversible reactions will reach chemical equilibrium
Fudgin [204]
True, all reversible reactions will reach chemical equilibrium. 
5 0
3 years ago
Other questions:
  • The chemical reaction 2Cu + O2 → 2CuO + 315 kJ is an _____ reaction. Endothermic, combustion Exothermic, combustion Endothermic,
    11·2 answers
  • Deciding that she was thirsty, Ms. Smith decided to mix up some lemonade using 2 tablespoons of lemonade, and 2 cups of water. W
    14·1 answer
  • Which equation shows the beta decay of a transuranium element
    9·1 answer
  • What is volume? What instrument is used to measure liquid volume? What formula is used to calculate the volume of a solid object
    8·1 answer
  • Which discovery did J. J. Thomson make that improved upon Dalton's atomic theory?
    14·1 answer
  • Darwin found that genetic drift was most likely to have an effect on variation in __________.
    14·2 answers
  • A solution has a pH of 11.75. Calculate the [H:0*] of the solution
    13·1 answer
  • OA) can never be seen from Earth
    13·1 answer
  • Which hypothesis regarding the origin of life on Earth suggests that oxidation-reduction (redox) reactions may be responsible fo
    12·1 answer
  • Which process is involved in deepwater currents?
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!