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
Sonbull [250]
3 years ago
6

1) Which of the following is an example of an endothermic process?

Chemistry
2 answers:
svp [43]3 years ago
6 0

<u>Answer:</u>

<u>For 1:</u> The correct answer is Option a.

<u>For 2:</u> The correct answer is (-2222) - [(-1182) + (-1144)] kJ

<u>Explanation:</u>

  • <u>For 1:</u>

Endothermic reactions are defined as the reactions in which energy is absorbed by the system.

Exothermic reactions are defined as the reactions in which heat is released by the system.

For the given options:

<u>Option a:</u> In this case, solid chocolate bar is meting with increase in temperature. Thus, it is absorbing heat from the surrounding and is considered as an endothermic reaction.

<u>Option b:</u> In this case, fruit are freezing in the freezer. Thus, it is releasing heat to the surrounding and is considered as an exothermic reaction.

<u>Option c:</u> Combustion reactions are defined as the reactions in which hydrocarbon reacts with oxygen gas to release carbon dioxide and water molecule with the release of heat. Thus, it considered as an exothermic reaction.

<u>Option d:</u> In this case, water molecules present in the air are getting condensed. Thus, it is releasing heat to the surrounding and is considered as an exothermic reaction.

From the above information, the correct answer is option a.

  • <u>For 2:</u>

According to Hess’s law, the heat absorbed or evolved in chemical equation is same whether the process is occuring in one step or in several steps.

According to this law, the chemical equation is treated as the ordinary algebraic expression which can be added or subtracted to get the required equation. This means the enthalpy change of the overall reaction will be equal to the sum of the enthalpy changes of the intermediate reactions.

We are given 3 intermediate balanced reactions:

Equation 1:  3C+3O_2\rightarrow 3CO_2;\Delta H_1=-1182kJ

Equation 2:  4H_2+2O_2\rightarrow 4H_2O;\Delta H_2=-1144kJ

Equation 3:  C_3H_8+5O_2\rightarrow 3CO_2+4H_2O;\Delta H_3=-2222kJ

Final Equation:  C_3H_8\rightarrow 3C+4H_2

By adding Equation 3 and reverse reaction of Equation 1 and Equation 2, we will get the enthalpy of final equation.

\Delta H_{final}=\Delta H_{3}-[\Delta H_1+\Delta H_2]\\\\\Delta H_{final}=-2222+[(-1182)+(-1144)]kJ

Hence, the correct answer is (-2222) - [(-1182) + (-1144)] kJ

Aleks04 [339]3 years ago
3 0
For the first question, the correct answer among the choices listed is option A, a chocolate bar melting in hot car. It is an endothermic process because it absorbs heat energy for it to be melted. For the second question, it think the correct answer is the last option, <span>(-2222) + (-1182) - (-1144).</span>
You might be interested in
What is the half life of an isotope that is 75% decayed after 16 days?
inna [77]

Answer:

half life will be 8days

5 0
2 years ago
You find a compound composed only of element X and chlorine and you know that the compound is 13.10% X by mass. Each molecule of
8_murik_8 [283]

Answer:

Explanation:

So, the formula for the compound should be:

XCl_{6}

Now we assume that we have 1 mol of substance, so we can make calculations to know the molar mass of element X, as follows:

M_{Cl}=35.45g/mol\\

So we have that 6 moles weight 212.7g, and we can make a rule of three to know the weight of compound X:

212.7g\rightarrow 86.9\%\\x\rightarrow 13.1\%\\\\x=\frac{212.7g*13.1}{86.9} =32.06g

As we used 1 mol, we know that the molar mass is 32.06g/mol

So the element has a molar mass of 32.06 g/mol and an oxidation state of +6, with this information, we can assure that the element X is sulfur, so the compound is SCl_{6}

8 0
3 years ago
How many seconds would it take to deposit 17.3 g of ag (atomic mass = 107.87) from a solution of agno3 using a current of 10.00
Brums [2.3K]
Data Given:

Time = t = ?

Current = I = 10 A

Faradays Constant = F = 96500

Chemical equivalent = e = 107.86/1 = 107.86 g

Amount Deposited = W = 17.3 g

Solution:
             According to Faraday's Law,

                                          W  =  I t e / F

Solving for t,

                                          t  =  W F / I e
Putting values,
                                          t  =  (17.3 g × 96500) ÷ (10 A × 107.86 g)

                                          t  =  1547.79 s

                                          t  = 1.54 × 10³ s
5 0
3 years ago
Details about outer ear
Verdich [7]
Outer ear is the is external part of the ear, consists of the auricle ( also pinna), and the ear canal. It gathers sound energy and focuses it on the ear drum.  
7 0
3 years ago
2. How many moles are in 2.8 Liters of CO2 gas?
andrew-mc [135]

Answer:

0.125 moles

Explanation:

2.8 litres is equivalent to 2.8dm³

At STP,

1 mole = 22.4 dm³

x mole = 2.8 dm³

Cross multiply

22.4x = 2.8

Divide both sides by 22.4

x = 2.8/22.4

x = 0.125

4 0
2 years ago
Other questions:
  • Write the formula and name of the compound formed from the following ionic interactions:
    13·1 answer
  • I need heLp ASAP
    7·2 answers
  • What is the unit of measurement used to express density
    8·1 answer
  • To isolate the benzoic acid from the bicarbonate solution, you should
    7·1 answer
  • The OH- ion concentration is greater than the H3o+ ion concentration in a water solution of
    12·1 answer
  • CHECK MY RECENT QUESTION HELP ME ASAP
    11·1 answer
  • What is the product of the following numbers? Use a scientific calculator to
    9·1 answer
  • Which statement most accurately describes a chemical equation?
    6·1 answer
  • Building Vocabulary
    9·1 answer
  • Sixty-three grams of copper reacted with 32 grams of sulfur. this chemical reaction produced the compound copper sulfide. what w
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!