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3 years ago

10pt if given the correct answer I will mark you as brainliest

Chemistry

2 answers:

diamong [38]3 years ago

3 0

Answer:

Explanation:

4(Al)+3(O2)==2(Al2O3)

Also, i'm in sixth grade just took a leson on a text book so may be wrong but i'm prety sure it's the correct nswer because x(Al)+y(O2) can not make hydregen for the h2o and for b, al+so2 = al2O3 makes sense but where did the sulfer go?

Keith_Richards [23]3 years ago

3 0

Answer:

C- 1, 2 and 5

Explanation:

There are many reactions that occur in the world, and one of the more important ones are known as combustion reactions. These reactions always involve the reaction between oxygen and another element/molecule/compound. So automatically, option 2 needs to be correct, so any answer that does not have option 2 in it (B) is incorrect.

Another important factor of combustion reactions is that they give off heat, because they are exothermic reactions, however since there is no indication of energy levels, so the answer in this question cannot be determined through that method.

One important law in all reactions is the conservation of matter, so whatever atoms enter the chemical reaction, have to exit the chemical reaction (no atoms can suddenly appear without having been there originally. For example, if only oxygen and hydrogen enter a reaction, only a product with oxygen and hydrogen can exit the reaction, it is impossible to have a product containing chlorine, if no chlorine was part of the reactants). By this logic, it is impossible to have water (H₂O) as a product, if the reactants are 1 and 2 (Al and O₂), hence option A is incorrect.

The only other option left is option C, and this option is correct because the overall balanced reaction would look like such:

4Al + 3O₂ --> 2Al₂O₃

This reaction obeys the law of conservation of matter, hence, Option C is correct.

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solution:

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6 0

3 years ago

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According to which theory or law is a chemical reaction most likely to occur when two particles with the proper energy and orien

Nat2105 [25]

<h2>Collision Theory </h2>

Explanation:

<h3>The given statement is related to the collision theory - </h3>

Collision theory was given by William Lewis in 1916.

This theory explains in a qualitative manner that in what way any chemical reaction occurs and the reason for the different reaction rates for different reactions.

<h3>According to the collision theory - </h3>

Molecules must collide in order to react
Sufficient amount of energy is needed for collisions (kinetic energy) so that the chemical bonds should break
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6 0

3 years ago

Keq for the reaction below is 2400. If the initial conditions of the reaction are a 1.0 L flask that contains 0.024 mol NO (g),

podryga [215]

Answer:

The answer to your question is it is not at equilibrium, it will move to the products.

Explanation:

Data

Keq = 2400

Volume = 1 L

moles of NO = 0.024

moles of N₂ = 2

moles of O₂ = 2.6

Process

1.- Determine the concentration of reactants and products

[NO] = 0.024 / 1 = 0.024

[N₂] = 2/1 = 2

[O₂] = 2.6/ 1= 2.6

2.- Balanced chemical reaction

N₂ + O₂ ⇒ 2NO

3.- Write the equation for the equilibrium of this reaction

Keq = [NO]²/[N₂][O₂]

- Substitution

Keq = [0.024]² / [2][2.6]

-Simplification

Keq = 0.000576 / 5.2

-Result

Keq = 1.11 x 10⁻⁴

Conclusion

It is not at equilibrium, it will move to the products because the experimental Keq was lower than the Keq theoretical-

1.11 x 10⁻⁴ < 2400

7 0

3 years ago

The half-life of a first-order reaction is 13 min. If the initial concentration of reactant is 0.085 M, how long would it take u

olasank [31]

Answer: It will take 8.2 minutes until the concentration decreases to 0.055 M

Explanation:

The time after which 99.9% reactions gets completed is 40 minutes

Explanation:

Expression for rate law for first order kinetics is given by:

$t=\frac{2.303}{k}\log\frac{a}{a-x}$

where,

k = rate constant

t = age of sample

a = let initial amount of the reactant

a - x = amount left after decay process

a) for completion of half life:

Half life is the amount of time taken by a radioactive material to decay to half of its original value.

$t_{\frac{1}{2}}=\frac{0.693}{k}$

$k=\frac{0.693}{13min}=0.053min^{-1}$

b) Time taken for 0.085 M to decrease to 0.055 M

$t=\frac{2.303}{0.053}\log\frac{0.085}{0.055}$

$t=8.2min$

Thus it will take 8.2 minutes until the concentration decreases to 0.055 M

5 0

3 years ago

50 points for this

GalinKa [24]

The inner core us the densest

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