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3 years ago

How do you do this? very confused

Chemistry

1 answer:

Vlad [161]3 years ago

4 0

The problem you have written you almost have it solved. Take the moles that you have calculated and multiply that by the molecular weight to get the grams.

The STP problem:
use the moles you calculated along with 1 atm for Pressure, and 273 for the temperature and plug into the PV = nRT equation. (also use 0.0821 for R)

From there you can solve for the volume

Hope this helps!

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One of the steps in the commercial process for converting ammonia to nitric acid is the conversion of NH3 to NO: 4NH3 (g) 5O2 (g

madreJ [45]

Answer:

O2 is the limiting reactant.

Explanation:

Step 1: Data given

Mass of NH3 = 2.00 grams

Mass of O2 = 2.50 grams

Molar mass NH3 = 17.03 g/mol

Molar mass O2 = 32 g/mol

Step 2: The balanced equation

4NH3(g) + 5O2 (g) → 4NO(g) + 6H2O (g)

Step 3: calculate moles NH3

Moles NH3 = mass NH3 / molar mass NH3

Moles NH3 = 2.00 grams / 17.03 g/mol

Moles NH3 = 0.117 moles

Step 4: Calculate moles O2

Moles O2 = mass / molar mass O2

Moles O2 = 2.50 grams / 32 g/mol

Moles O2 = 0.0781 moles

Step 5: Calculate the limiting reactant

For 4 moles NH3 we need 5 moles O2 to produce 4 moles NO and 6 moles H2O

O2 is the limiting reactant. It will completely be consumed. (0.0781 moles). NH3 is in excess. There will react 4/5 * 0.0781 moles = 0.0625 moles

There will remain 0.117 - 0.0625 = 0.0545 moles NH3

O2 is the limiting reactant.

8 0

3 years ago

For the reaction of oxygen and nitrogen to form nitric oxide, consider the following thermodynamic data (Due to variations in th

CaHeK987 [17]

Answer:

a. 7278 K

b. 4.542 × 10⁻³¹

Explanation:

Let´s consider the following reaction.

N₂(g) + O₂(g) ⇄ 2 NO(g)

The reaction is spontaneous when:

ΔG° < 0 [1]

Let's consider a second relation:

ΔG° = ΔH° - T × ΔS° [2]

Combining [1] and [2],

ΔH° - T × ΔS° < 0

ΔH° < T × ΔS°

T > ΔH°/ΔS°

T > (180.5 × 10³ J/mol)/(24.80 J/mol.K)

T > 7278 K

First, we will calculate ΔG° at 25°C + 273.15 = 298 K

ΔG° = ΔH° - T × ΔS°

ΔG° = 180.5 kJ/mol - 298 K × 24.80 × 10⁻³ kJ/mol.K

ΔG° = 173.1 kJ/mol

We can calculate the equilibrium constant using the following expression.

ΔG° = - R × T × lnK

lnK = - ΔG° / R × T

lnK = - 173.1 × 10³ J/mol / (8.314 J/mol.K) × 298 K

K = 4.542 × 10⁻³¹

7 0

3 years ago

Assume the weight of an average adult is 70. kg, and that 420. kJ of heat are evolved per mole of oxygen consumed as a result of

seraphim [82]

Answer:

The temperature difference of the body after 3 hours = 5.16 K

Explanation:

we know that the number of moles of O₂ inhaled are 0.02 mole/min⁻¹

or, 1.2 mole.h⁻¹

The average heat evolved by the oxidation of foodstuffs is then:

⇒ Q avg = $\frac{1.2 X 420 X 10^{3} }{70}$ = 7.2 kj.h⁻¹.Kg⁻¹

the heat produced after 3 h would be:

= 7.2 kj. h⁻¹.Kg⁻¹ x 3 h

= 21.6 kj. kg⁻¹

= 21.6 x 10³ j kg⁻¹

We know Qp = Cp x ΔT

Assume the heat capacity of the body is 4.18 J g⁻¹K⁻¹

⇒ ΔT = $\frac{Qp}{Cp}$

⇒ ΔT = $\frac{(21.6 X 10^{3} j.kg^{-1} ) }{(4.18 j k^{-1}g^{-1}) X (1000g.kg^{-1} )}$

⇒ ΔT = 5.16 K

6 0

3 years ago

Radioactive decay can be described by the following equation where is the original amount of the substance, is the amount of the

soldi70 [24.7K]

Answer:

Iron remains = 17.49 mg

Explanation:

Half life of iron -55 = 2.737 years (Source)

$t_{1/2}=\frac {ln\ 2}{k}$

Where, k is rate constant

So,

$k=\frac {ln\ 2}{t_{1/2}}$

$k=\frac {ln\ 2}{2.737}\ year^{-1}$

The rate constant, k = 0.2533 year⁻¹

Time = 2.41 years

$[A_0]$ = 32.2 mg

Using integrated rate law for first order kinetics as:

$[A_t]=[A_0]e^{-kt}$

Where,

$[A_t]$ is the concentration at time t

$[A_0]$ is the initial concentration

So,

$[A_t]=32.2\times e^{-0.2533\times 2.41}\ mg$

$[A_t]=32.2\times e^{-0.610453}\ mg$

$[A_t]=17.49\ mg$

<u>Iron remains = 17.49 mg</u>

8 0

3 years ago

according to the third law if a football player hits another player with an action force of 1500n how much will the reaction for

djyliett [7]

Answer:

The reaction would be 1500n (equal reaction)

Explanation:

This can be explained by Newton's third law of motion which states that for every action (force), there is an opposite and equal reaction. In other words, when two objects or people come in contact, the magnitude of force which they exert on each other is equal and they both feel an equal reaction force.

It doesn't matter whether one of the colliding bodies is of bigger mass than the other. This Newton's third law of motion is also known as the law of action and reaction.

3 0

2 years ago