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3 years ago

Someone help me please!!!!!!

Chemistry

1 answer:

uysha [10]3 years ago

5 0

Answer:

1.67 moles SiC

Explanation:

Given Rxn SiO₂ + 3C => SiC + 2CO

Given mass => 5 moles C => ? moles SiC will be formed

Mass (moles) SiC yield = 1/3(5moles) = 1.67moles SiC

Solution Analysis:

Look at the balanced equation and note the coefficients of the given and unknown. In the above case, the balanced equation shows 3 moles Carbon to 1 mole Silicon Carbide. Since the coefficient for SiC is smaller than the coefficient for C then one should get a yield of SiC smaller than moles of C given. To calculate the yield based on these two compounds make a ratio of coefficients such that when multiplied by the given (5 moles in this case) one obtains a number smaller than 5. That is, 1/3(5 moles) = 1.67 moles SiC. Note that the moles of SiC (=1.67) is smaller than moles of C (=5 moles). You certainly would not get a smaller number than 5 if you used the ratio 3/1(5) moles = 15 moles. Wrong!

Here’s another example:

Given Rxn => 3H₂ + N₂ => 2NH₃

Given 7 moles H₂ calculate the moles of NH₃ produced.

Solution:

Note the known is moles H₂ and NH₃ the unknown. From the balanced equation note the coefficient of NH₃ is smaller than the coefficient for H₂. Therefore using the coefficients of H₂ (3) and NH₃ (2) form a ratio such that when multiplied by the given 7 moles one gets a smaller number (the answer needed).

Therefore, mass (moles) NH₃ produced = 2/3(7) moles NH₃ = 3.33 moles NH₃ produced from 7 moles of H₂. 3.33 < 7 as defined by balanced equation.

Rule of Thumb...

When working equation problems, first convert all given data to moles and then use the ratio of coefficients to make the given smaller or larger as defined by equation. Then, if needed, convert moles to desired dimension for problem given.

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Helppppp pleaseeee xxxxxx

kogti [31]

Answer:

2812.6 g of H₂SO₄

Explanation:

From the question given above, the following data were obtained:

Mole of H₂SO₄ = 28.7 moles

Mass of H₂SO₄ =?

Next, we shall determine the molar mass of H₂SO₄. This can be obtained as follow:

Molar mass of H₂SO₄ = (1×2) + 32 + (16×4)

= 2 + 32 + 64

= 98 g/mol

Finally, we shall determine the mass of H₂SO₄. This can be obtained as follow:

Mole of H₂SO₄ = 28.7 moles

Molar mass of H₂SO₄ =

Mass of H₂SO₄ =?

Mole = mass / Molar mass

28.7 = Mass of H₂SO₄ / 98

Cross multiply

Mass of H₂SO₄ = 28.7 × 98

Mass of H₂SO₄ = 2812.6 g

Thus, 28.7 mole of H₂SO₄ is equivalent to 2812.6 g of H₂SO₄

3 0

3 years ago

A battery has an electrical ______________ energy

aleksley [76]

Answer:

Electrical Energy

Explanation:

There are a variety of chemical and mechanical devices that are called batteries, although they operate on different physical principles. A battery for the purposes of this explanation will be a device that can store energy in a chemical form and convert that stored chemical energy into electrical energy when needed.

5 0

3 years ago

1.) The process for converting ammonia to nitric acid involves the conversion of NH3 to

Firdavs [7]

Answer:

a) 1.39 g ; b) O₂ is limiting reactant, NH₃ is excess reactant; c) 0.7 g

Explanation:

We have the masses of two reactants, so this is a limiting reactant problem.

We will need a balanced equation with masses, moles, and molar masses of the compounds involved.

1. Gather all the information in one place with molar masses above the formulas and masses below them.

MM: 17.03 32.00 30.01

4NH₃ + 5O₂ ⟶ 4NO + 6H₂O

Mass/g: 1.5 1.85

2. Calculate the moles of each reactant

$\text{moles of NH}_{3} = \text{1.5 g NH}_{3} \times \dfrac{\text{1 mol NH}_{3}}{\text{17.03 g NH}_{3}} = \text{0.0881 mol NH}_{3}\\\\\text{moles of O}_{2} = \text{1.85 g O}_{2} \times \dfrac{\text{1 mol O}_{2}}{\text{32.00 g O}_{2}} = \text{0.057 81 mol O}_{2}$

3. Calculate the moles of NO we can obtain from each reactant

From NH₃:

The molar ratio is 4 mol NO:4 mol NH₃

$\text{Moles of NO} = \text{0.0881 mol NH}_{3} \times \dfrac{\text{4 mol NO}}{\text{4 mol NH}_{3}} = \text{0.0881 mol NO}$

From O₂:

The molar ratio is 4 mol NO:5 mol O₂

$\text{Moles of NO} = \text{0.057 81 mol O}_{2}\times \dfrac{\text{4 mol NO}}{\text{5 mol O}_{2}} = \text{0.046 25 mol NO}$

4. Identify the limiting and excess reactants

The limiting reactant is O₂ because it gives the smaller amount of NO.

The excess reactant is NH₃.

5. Calculate the mass of NO formed

$\text{Mass of NO} = \text{0.046 25 mol NO}\times \dfrac{\text{30.01 g NO}}{\text{1 mol NO}} = \textbf{1.39 g NO}$

6. Calculate the moles of NH₃ reacted

The molar ratio is 4 mol NH₃:5 mol O₂

$\text{Moles reacted} = \text{0.057 81 mol O}_{2} \times \dfrac{\text{4 mol NH}_{3}}{\text{5 mol O}_{2}} = \text{0.046 25 mol NH}_{3}$

7. Calculate the mass of NH₃ reacted

$\text{Mass reacted} = \text{0.046 25 mol NH}_{3} \times \dfrac{\text{17.03 g NH}_{3}}{\text{1 mol NH}_{3}} = \text{0.7876 g NH}_{3}$

8. Calculate the mass of NH₃ remaining

Mass remaining = original mass – mass reacted = (1.5 - 0.7876) g = 0.7 g NH₃

8 0

3 years ago

What stress will shift the following equilibrium system to the left?

Alona [7]

Answer: Increasing temperature

Explanation:

The Principle of Le Chatelier states that if a system in equilibrium is subjected to a change of conditions, it will move to a new position in order to counteract the effect that disturbed it and recover the state of equilibrium.

The variation of one or several of the following factors can alter the equilibrium condition in a chemical reaction:

Temperature
The pressure
The volume
The concentration of reactants or products

In the case of the reaction in the question, the change that moves the balance to the left will be the one that moves it towards the reagents, that is, that favors the production of reagents instead of products.

Decreasing the concentration of SO3 and increasing the concentration of SO2 will favor the production of SO3, which is the product of the reaction.
Decreasing the volume increases the pressure of the system and the balance will move to where there is less number of moles. In the case of the reaction in question, we have 3 moles of molecules in the reactants (1 mole of O2 + 2 moles of SO2) while in the products there are 2 moles of SO3 only, therefore, decreasing the volume will displace the balance to the right, which corresponds to the sense in which there is less number of moles.

The reaction of the question is an exothermic since ΔH <0, therefore in the reaction heat is produced and it can be written in the following way,

2SO2(g) + O2(g) ⇌ 2SO3(g) + heat

So, if we increase the temperature we will be adding heat to the system, so the balance would move to the left to compensate for the excess heat in the system.

5 0

3 years ago

Ayudameeeee Jorge AhAaaAA

Gelneren [198K]

Ok what you want. I got u

5 0

3 years ago

Read 2 more answers