CHEMISTRY COLLEGE

Determine total H for bonds broken and formed, the overall change in H, and the final answer with units. Is it ENDOthermic or EXOthermic? Reaction:
2H2(g) +O2(g) -> 2H2O^(g)
Given:
H-H 436
O+O 499
O-H 463

Answers

Answer 1
Answer:
  • E(Bonds broken) = 1371 kJ/mol reaction
  • E(Bonds formed) = 1852 kJ/mol reaction
  • ΔH = -481 kJ/mol.
  • The reaction is exothermic.

Explanation

2 H-H + O=O → 2 H-O-H

There are two moles of H-H bonds and one mole of O=O bonds in one mole of reactants. All of them will break in the reaction. That will absorb

  • E(Bonds broken) = 2 × 436 + 499 = 1371 kJ/mol reaction.
  • ΔH(Breaking bonds) = +1371kJ/mol

Each mole of the reaction will form two moles of water molecules. Each mole of H₂O molecules have two moles O-H bonds. Two moles of the molecule will have four moles of O-H bonds. Forming all those bond will release

  • E(Bonds formed) = 2 × 2 × 463 = 1852kJ/mol reaction.
  • ΔH(Forming bonds) = - 1852 kJ/mol

Heat of the reaction:

  • \Delta H_{\text{rxn}} = \Delta H(\text{Breaking bonds}) + \Delta H(\text{Forming bonds})\n\phantom{ \Delta H_{\text{rxn}}} = +1371 + (-1852) \n\phantom{ \Delta H_{\text{rxn}}} = -481 \; \text{kJ} / \text{mol}

\Delta H_{\text{rxn}} is negative. As a result, the reaction is exothermic.

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A spontaneous reaction occurs

Answers

Answer:

A spontaneous reaction is a reaction that occurs in a given set of conditions without intervention. A spontaneous reactions are accompanied by an increase in overall entropy, or disorder

Explanation:

Which of the following characterizes a reaction at equilibrium?A. The forward reaction stops, and the backward reaction starts.
B. The forward and backward reactions are equal.
C. The forward and backward reactions stop happening.
D. The reactants are changed into products.
SUBMIT

Answers

At chemical equilibrium,the forward and backward reactions are equal and opposite.

What is chemical equilibrium?

Chemical equilibrium is defined as the condition which arises during the course of a reversible chemical reaction with no net change in amount of reactants and products.A reversible chemical reaction is the one wherein the products as soon as they are formed react together to produce back the reactants.

At equilibrium, the two opposing reactions which take place take place at equal rates and there is no net change in amount of the substances which are involved in the chemical reaction.At equilibrium, the reaction is considered to be complete . Conditions which are required for equilibrium are given by quantitative formulation.

Factors which affect chemical equilibrium are change in concentration , change in pressure and temperature and presence of catalyst.

Learn more about chemical equilibrium,here:

brainly.com/question/3920294

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B. The forwards and backwards motions are equal

How much energy in joules does it take to raise the temperature of 255g of water by 12.5C

Answers

Energy in a system can be calculated by multiplying the given mass to thespecific heat capacity of the substance and the temperature difference. It isexpressed as follows:

Energy = mC(T2-T1)
Energy = 255(4.184)(12.5)
Energy = 13336.5 J

Answer: The amount of energy required to raise the temperature is 13323.75 joules.

Explanation :

The amount of energy required to raise the temperature can be calculated as follows.

                   q = m* C* \bigtriangleup T

where,

        q = heat energy

        m = mass of water

         C = specific heat

          T = temperature

Remember that the specific heat of water is 4.18\left ( (J)/(g^\circ C)} \right ).

Therefore, putting the values in the above equation as follows.

        q = m* C* \bigtriangleup T

           = 255 g * 4.18 \left ( (J)/(^\circ C)} \right )* 12.5^oC

         = 13323.75 joules

So, the amount of energy required to raise the temperature is 13323.75 joules.

Choose all the answers that apply. Which of the following is true about the sun's radiation? A) It is long-wave.
B) It is short-wave.
C) 40 percent is reflected by the atmosphere.
D) 60 percent reaches Earth's surface.
E) None of the rays are harmful.

Answers

B. It is shortwave.....

Answer:

Your answers are B,C, and D

Explanation:

Because a and e are wrong it is these three.

Edit pls mark brainliest

Copper and iron(III) nitrate
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Answers

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Systematic name for: Silver Nitrate.molar mass of Ag:
molar mass of N:
molar mass of O:

and the overall molar mass for Silver Nitrate.

Answers

Answer:

AgNO_3 ,Molar mass =169.87 g/mol

Explanation:

The systematic name for silver nitrate is AgNO_3

Now we have to calculate the molar mass of  AgNO_3

Molar mass of Ag = 107.87 g/mol

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=(1* 107.87+1* 14+3* 16)=169.87g/mol
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