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Answer: Option (b) is the correct answer.

Explanation:

When thermal energy is added to a substance then there will occur an increase in the kinetic energy of molecules. As a result, motion of particles increases due to which a solid substance changes into liquid state and a liquid substance changes into gaseous state.

When a liquid substance gets converted into vapors or gaseous state then this process is called vaporization.

Thus, phase changes that requires the addition of thermal energy is vaporization.

Answer:

NH₃ is limiting reactant .

Explanation:

Given data:

Number of moles of NH₃ = 45 mol

Number of moles of NO₂ = 50 mol

Limiting reactant  = ?

Solution:

Chemical equation:

8NH₃ + 6NO₂        →      7N₂  + 12H₂O

Now we will compare the mole of reactants with products.

               NH₃           ;          N₂

                 8              :          7

               45              :        7/8×45 = 39.4 mol

                NH₃           ;         H₂O

                 8              :          12

               45              :        12/8×45 = 67.5 mol

               NO₂           ;          N₂

                 6              :          7

               50              :        7/6×50 = 58.3 mol

               NO₂           ;         H₂O

                 6              :          12

               50              :        12/6×50 = 100 mol

Less number of moles of product are formed by the ammonia thus it will be limiting reactant.

Answer:

protons, neutrons, and electrons

Explanation:

protons have a positive charge, neutrons have a neutrel charge, and electrons have a negative charge

Answer:

Light receptors within the eye transmit messages to the brain, which produces the familiar sensations of color. The surface of an object reflects some colors and absorbs all the others. We perceive only the reflected colors.

Explanation:

go.ogle :)

The abundance of isotope 35 = 75%

The abundance of isotope 37 = 25%

Ratio isotope 35 :  isotope 37 = 3 : 1

Given

Ar Cl = 35.5

Two isotopes of mass number 35 and 37

Required

The ratio of each isotope

Solution

If the abundance of isotope 35 is x%, then the abundance of isotope 37 is (100-x)%

35.5 = x%.35 + (100-x)%.37

35.5 = 0.35x+0.37(100-x)

35.5=0.35x-0.37x+37

0.02x=1.5

x=75

Answer:

A

Explanation:

Answer:

You need to make sure the number of atoms of each element on the reactant side is equal to the number of atoms of each element on the product side. In order make both sides equal, you will need to multiply the number of atoms in each element until both sides are equal. :)

Answer:

Sublimation is a physical change. When a substance sublimes, it changes from a solid to a gas without going through the liquid phase.

Explanation:

Answer:

1. A. 0

2. B. 7

3. C. 4

Explanation:

1. charge is equal to the number of protons minus the number of electrons!

2. neutrons is equal to mass number minus atomic number!

3. valence electrons equal 4!

Hope this helped you! :)

A fuel cell require a continuous input of fuel and an oxidizing agent in order to sustain the reactions which generate the electricity. The item in which  fuel cells more commonly used is propane lanterns. The correct option is D.

The propane lanterns is one of the gas interns which is a lightweight portable device which supplies bright efficient light while protecting its contents from wind and brain. The gas interns are incandescent lights.

The gas interns burn fuel like propane, white gas or kerosene to generate heat and the heat causes the mantles to produce light. The mantles are defined as the ceramic mesh which encase the flame produced by the lantern.

The gas lanterns are very simple, any heated material will produce light. The lantern burns fuel to produce heat. The gas lanterns use mantles instead of limestone blocks. The mantles are highly efficient at producing light from the heat they acquire.

Thus the correct option is D.

To know more about fuel cell, visit;

https://brainly.com/question/28329395

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Answer:

hydrogen oxygen carbon and nitrogen

Hope my answer helps you.

Moles of Ammonia (NH₃) in solution = 1.14

Given

0.175 L of 6.50 M aqueous ammonia

Required

moles of ammonia

Solution

Ammonia = NH₃

Molarity = moles of solute per liter of solution

[tex]\tt M=\dfrac{n}{V}[/tex]

n = M x V

n = 6.50 M x 0.175 L

n = 1.1375 moles

In a multiplication operation: the significant digits in the final product must follow the number of significant digits that are at least in the numbers involved in multiplying

6.50 = 3 sig fig

0.175 = 3 sig fig

So the result must be 3 sig fig

1.1375 rounded to 1.14

Answer:

The kinetic energy of an object is also measured in joules. Anything that is moving has kinetic energy, but various factors affect how much kinetic energy an object has. The first factor is speed. If two identical objects are moving at different speeds, the faster object has more kinetic energy.  In physics, the kinetic energy  of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. The same amount of work is done by the body when decelerating from its current speed to a state of rest.

Explanation:

Answer: Potential energy is a little different. It is the energy an object has the potential to create. The energy produced is determined similarly to kinetic. It depends on the object's mass, the gravitational pull when up or down slopes, and the height of the reference point.

another explanation:

a) Potential Energy:

mass and height

We know that potential energy, PE is equal to the product of the mass, the gravitational acceleration and the height.

Since gravity is constant, the mass and height are the factors.

b) Kinetic Energy:

The mass (m) of the object and the speed (v) of the object.

Because kinetic energy is proportional to the velocity squared, increases in velocity will have an exponentially greater effect on transitional kinetic energy. Doubling the mass of an object will only double its kinetic energy, but doubling the velocity of the object will quadruple its velocity.

Answer:

It's an element.

Explanation:

Au is gold. An "element " on the periodic table. Trust me. Im 100% sure.

Explanation:

gold is an element

{au 79 is the atomic number}

Answer:

a. forces acting on the object

Answer:

It would be false because there are series circuit that only has one path

Answer:

I believe Gases A and D

Explanation:

The lines in both gases match up with the lines in the unknown mixture.

Answer:

Fa (rt) and Nitrogen

Explanation:

Answer:

the force needed to produce the same acceleration is 480kg

Answer:

Molecular Formulas for Compounds

Explanation:

Answer:

6th period

Explanation:

Answer:

1813.74g

Explanation:

Given parameters:

Number of moles of radon  = 8.17moles

Unknown:

Mass of radon  = ?

Solution:

To solve this problem, we use the expression below:

      Number of moles = [tex]\frac{mass}{molar mass}[/tex]  

Molar mass of radon  = 222g/mol

Now insert the parameters and solve;

    Mass of radon  = Number of moles x molar mass

                              = 8.17 x 222

                              = 1813.74g

Answer: [tex]_{38}^{90}\textrm{Sr}\rightarrow _{36}^{86}\textrm{Kr}+_2^4\textrm{He}[/tex]

Explanation:

Alpha Decay: In this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. The mass number is reduced by 4 units and atomic number is reduced by 2 units.

General representation of an element is given as:   [tex]_Z^A\textrm{X}[/tex]

where,

Z represents Atomic number

A represents Mass number

X represents the symbol of an element

General representation of alpha decay :

[tex]_Z^A\textrm{Sr}\rightarrow _{Z-2}^{A-4}Y+_2^4\alpha[/tex]

The  balanced nuclear equation when the isotope Strontium-90 decays by Q-  decay is :

[tex]_{38}^{90}\textrm{Sr}\rightarrow _{36}^{86}\textrm{Kr}+_2^4\textrm{He}[/tex]

Answer: Option (b) is the correct answer.

Explanation:

It is known that,

                   pH + pOH = 14

So, pOH = 14 - pH

As the given pH is 9.3. Hence, pOH for the given solution will be calculated as follows.

          pOH = 14 - 9.3

                   = 4.7

Therefore, pOH of the given solution is 4.7.

Answer:

covalent

Explanation:

Answer:

A Watershed

Explanation:

A watershed consists of all the land that supplies water to a river system

Answer:

watershed

Explanation: