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Find ΔHrxn for the following reaction: 2PbS(s)+3O2(g)→2PbO(s)+2SO2(g)

ch4aika [34]

Answer:

ΔH°rxn = -827.5 kJ

Explanation:

Let's consider the following balanced equation.

2 PbS(s) + 3 O₂(g) → 2 PbO(s) + 2 SO₂(g)

We can calculate the standard enthalpy of reaction (ΔH°rxn) from the standard enthalpies of formation (ΔH°f) using the following expression.

ΔH°rxn = [2 mol × ΔH°f(PbO(s)) + 2 mol × ΔH°f(SO₂(g) )] - [2 mol × ΔH°f(PbS(s)) + 3 mol × ΔH°f(O₂(g) )]

ΔH°rxn = [2 mol × (-217.32 kJ/mol) + 2 mol × (-296.83)] - [2 mol × (-100.4) + 3 mol × 0 kJ/mol]

ΔH°rxn = -827.5 kJ

5 0

3 years ago

A pure compound is found to be 40.0% carbon by mass, 6.73% hydrogen by mass, and 53.3% oxygen by mass. determine the empirical f

ratelena [41]

Since there is no weight, I would assume that this is a 100g of pure compound.
Okay so I would be changing the percentage to gram to solve for the mole.
So
40.0g C (1 mol C/12.01 g C) = 3.33 mol C
6.73g H (1 mol H/1.01 g H ) = 6.66 mol H
53.3g O (1 mol O/16.00 g O) = 3.33 mol O

With that, two of our moles is 3.33, so we consider that are our 1, as it is also the lowest. Therefore the empirical formula is CH2O

3 0

3 years ago

Which is an example of a chemical change? vaporization of water none of these are examples of a chemical change sublimation of d

Anit [1.1K]

Digesting of food because stomaci acid reaction makes things melt w/ enzymes

5 0

4 years ago

Consider the process used to produce iron metal from its ore.

Dmitry_Shevchenko [17]

Answer:

223.4 grams of iron can be produced from 2.5 moles of Fe2O3 and 6.0 moles of CO.

Explanation:

The balanced reaction is:

Fe₂O₃ (s) + 3 CO(g) → 2 Fe(s) + 3 CO₂ (g)

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of reactant and product participate in the reaction:

Fe₂O₃: 1 mole
CO: 3 moles
Fe: 2 moles
CO₂: 3 moles

Being:

Fe: 55.85 g/mole
O: 16 g/mole
C: 12 g/mole

the molar mass of the compounds participating in the reaction is:

Fe₂O₃: 2*55.85 g/mole + 3*16 g/mole= 159.7 g/mole
CO: 12 g/mole + 16 g/mole= 28 g/mole
Fe: 55.85 g/mole
CO₂: 12 g/mole + 2*16 g/mole= 44 g/mole

Then, by stoichiometry of the reaction, the following quantities participate in the reaction:

Fe₂O₃: 1 mole* 159.7 g/mole= 159.7 g
CO: 3 moles* 28 g/mole= 84 g
Fe: 2 moles* 55.85 g/mole= 111.7 g
CO₂: 3 moles* 44 g/mole= 132 g

The limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.

So, first of all, you can apply the following rule of three: if by reaction stoichiometry 1 mole of Fe₂O₃ reacts with 3 moles of CO, then 2.5 moles of Fe₂O₃ react with how many moles of CO?

$moles of CO=\frac{2.5 moles of Fe_{2} O_{3}*3 moles of CO }{1 mole of Fe_{2} O_{3}}$

moles of CO= 7.5

But 7.5 moles of CO are not available, 6.0 moles are available. Since you have less moles than you need to react with 2.5 moles of Fe₂O₃, CO will be the limiting reagent.

Now you can apply the following rule of three: if by reaction stoichiometry 3 moles of CO produce with 111.7 grams of Fe, then 6 moles of CO will produce how much mass of Fe?

$mass of Fe=\frac{6 moles of CO*111.7 grams of Fe}{3 moles of CO}$

mass of Fe= 223.4 grams

223.4 grams of iron can be produced from 2.5 moles of Fe2O3 and 6.0 moles of CO.

5 0

3 years ago

*WILL MARK BRAINLIEST! Why is it difficult for us to use fusion reactions to produce energy?

kolbaska11 [484]

Fusion occurs constantly on our sun, which produces most of its energy via the nuclear fusion of hydrogen into helium. Neither do fusion reactions produce the large amounts of dangerous radioactive waste that fission reactions do. That's why it's such a dreamy source of energy.

7 0

4 years ago