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3 years ago

Qué tipo de reacciones pertenecen las combustiones?

Chemistry

1 answer:

navik [9.2K]3 years ago

5 0

Answer:

Si una reacción química libera energía, se llama reacción exotérmica. El ejemplo más común es la combustión, en la cual la energía se manifiesta en forma de calor y luz. Si, por el contrario, la reacción química requiere energía del medio para efectuarse, recibe el nombre de reacción endotérmica.

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Consider the following reaction at constant P. Use the information here to determine the value of Î”Ssurr at 355 K. Predict whet

Sloan [31]

The given reaction is as follows:

2NO (g) + O₂ (g) = 2NO₂ (g), ΔH = -114 kJ

It is known that dSsurr = -dHsys / T (Temp = 355 K)

So, dSsurr = - (-114 × 1000) / 355

dSsurr = +321.12 J/K

Hence, the value of dSsurr is +321.12 J/K

For a reaction to be spontaneous, dG<0,

Also dStotal = dSsys + dSsurr > 0

It is known that dG = dHsys - TdSsys,

Now let us assume,

dG<0

Also, dStotal = dSsys + dSsurr > 0

(-114 × 1000) - (355 × dSsys) <0

355 × dSsys > -114 × 1000

dSsys > -321

dSsys >dSsurr

dSsys + dSsurr > 0

dStotal > 0

Thus, the assumption is correct, and the given reaction is spontaneous. Hence, the final answer is Ssurr = +321 J/K reaction is spontaneous.

8 0

3 years ago

How do you obtain oxide from a mixture?

emmainna [20.7K]

By direct heating of an element with oxygen : many metals and non-. metals burn rapidly when heated in oxygen or air producing their oxides e.g.

3 0

3 years ago

Why do atoms form bonds or why do bonds form?

stiv31 [10]

Answer:

Atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. A chemical bond is a force of attraction between atoms or ions

Explanation:

7 0

3 years ago

A box is 1 m high, 2.5 m long, and 1.5 m wide, its volume is 5 mº. true or false

Maurinko [17]

Answer:

false

Explanation:

Because volume is in m3

5 0

3 years ago

Read 2 more answers

If the mass of the baking soda before the reaction was 10 grams and the mass of the vinegar was 15 grams and all of the baking s

Masteriza [31]

Answer:

8.946g NaHCO₃,

14.475g H₂O,

1.025g CH₃COO⁻Na⁺,

0.500g CO₂.

Explanation:

Baking soda (NaHCO₃) reacts with vinegar (CH₃COOH 5%) producing CH₃COO⁻Na⁺, H₂O and CO₂, thus:

NaHCO₃ + CH₃COOH → CH₃COO⁻Na⁺ + H₂O + CO₂

10g of NaHCO₃ are:

10g × (1mol / 84g) = 0.119 moles NaHCO₃

Moles of CH₃COOH in 15g of vinegar are:

15g vinegar × 5% = 0.75g CH₃COOH × (1mol / 60g) = 0.0125moles CH₃ COOH

After reaction, moles of NaHCO₃ that remains are:

0.119mol - 0.0125mol = 0.1065 moles NaHCO₃

In mass:

0.1065mol ₓ (84g / 1mol) = 8.946g NaHCO₃

Acetic acid reacts completely producing 0.0125moles of CH₃COO⁻Na⁺, water and CO₂. In mass:

CH₃COO⁻Na⁺ = 0.0125mol ₓ (82.03g / 1mol) = 1.025g CH₃COO⁻Na⁺

H₂O = 0.0125mol ₓ (18.01g / 1mol) = 0.225g H₂O

CO₂ = 0.0125mol ₓ (40g / 1mol) = 0.500g CO₂

Now, 95% of vinegar is water (Doesn't react), that is:

15g × 95% = 14.25g H₂O. Total mass of water is:

14.25g + 0.225g = 14.475g H₂O

Total mass is:

8.946g + 14.475g H₂O + 1.025g + 0.500g ≈ 25g. The same than initial mass following law of conservation of matter.

6 0

3 years ago