How many photons are produced in a laser pulse of 0.203 J at 553 nm?

Answer:

Use the observations about each chemical reaction in the table below to decide the sign (positive or negative) of the reaction enthalpy AH and reaction entropy AS. Note: if you have not been given enough information to decide a sign, select the "unknown" option observations conclusions reaction ΔΗ is (pick one) The reverse of this reaction is always spontaneous. A As is (pick one) This reaction is spontaneous except below ΔΗ is (pick one) 38. °C but proceeds at a faster rate above (pick one) 91. °C As is ΔΗ iS (pick one) Crystallization of a pure compound is C spontaneous only below 146. °C. AS is (pick one) X

Answer:

Explanation:

a

The question is incomplete, the complete question is;

1.000 atm of Oxygen gas, placed in a container having apinhole opening in its side. leaks from the container 2.14 timesfaster thatn 1.000 atm of an unknown gas placed in this sameapparatus. Which of the following species could be theunknown gas?

A. CL2

B. SF6

C. Kr

D. UF6

E. Xe

Answer:

SF6

Explanation:

From Graham's law;

Let the rate of diffusion of oxygen be R1

Let the rate of diffusion of unknown base be R2

Let the molar mass of oxygen by M1

Let the molar mass of unknown gas be M2

Hence;

R1/R2 = √M2/M1

So;

2.14/1 = √M2/32

(2.14/1)^2 = M/32

M= (2.14/1)^2 × 32

M= 146.6

This is the molar mass of SF6 hence the answer above.

Answer:

all of the above

Explanation:

have a nice day :-)

Answer:

Explanation:

Hope this helps

Answer:

solo I

Explanation:

Según esta teoría para que se produzca una reacción deben cumplirse tres condiciones: Las moléculas de los reactivos tienen que chocar entre sí. Estos choques deben de producirse con energía suficiente de forma que se puedan romper y formar enlaces químicos.

Answer:

Wearing gloves

Explanation:

it helps on not touching chemicals

Answer:

Final pressure = 6 atm

Final volume = 1.1 L

Final temperature = 100 K

Explanation:

We are given;

Initial Pressure; P1 = 2 atm

Initial volume; V1 = 3.3 L

Initial temperature; T1 = 27° C + 273 = 300 K

Final pressure; P2 = 6 atm

We will use Boyles law to get the final volume.

P1V1 = P2V2

V2 = (P1 × V1)/P2

P2 = (2 × 3.3)/6

V2 = 1.1 L

We can use Charles law to find the final temperature.

V1/T1 = V2/T2

T2 = (V2 × T1)/V1

T2 = (1.1 × 300)/3.3

T2 = 100 K

Answer:

Light can be treated like particles because it is made of chunks like things called protons.

Answer:

the correct answer is four decimal places

Answer:

I don't no answer sorry

Explanation:

you follow me

Answer:

Before the equivalence point, conductivity is decreasing. After the equivalence point, conductivity is increasing

Explanation:

In solution H2SO3 produce H+ ions and SO3²⁻ ions. In the same way, NaOH produce Na⁺ and OH⁻ ions. The conductivity of a solution is directly proportional to the concentration of ions in a solution. During titration, you are adding more NaOH (That is, more Na⁺ and OH⁻ ions). But each moles of OH⁻ reacts with H⁺ ion producing H₂O. That means the moles of Na⁺ that you are adding = Moles of H⁺ are been consumed. The concentration of ions remains approximately constant. But, H⁺ ion conducts better than Na⁺ ion. That means before the equivalence point, conductivity is decreasing. But after the equivalence point you will add OH- ions in excess increasing ion concentration increasing the conductivity:

After equivalence point, conductivity is increasing.

Answer:

Global Warming

Explanation:

The biggest concern for environmental scientists is Global Warming. Our Earth is getting warmer which is having drastic effects on our planet. Such effects include increased natural fires, decreased water supply, decreased farm yields, increased floodings, etc. Global Warming poses a huge threat to humanity and it is because of humanity's constant and ever growing usage of fossil fuels that Global Warming is becoming such a threat. This is what environmental scientists are mainly focused on.

Answer:

2.4 × 10⁻⁴ M

Explanation:

Step 1: Calculate the concentration of Mg²⁺ coming from Mg(NO₃)₂

Mg(NO₃)₂ is a strong electrolyte and the molar ratio of Mg(NO₃)₂ to Mg²⁺ is 1:1. The initial molar concentration of Mg²⁺ is 1/1 × 0.36 M = 0.36 M.

Step 2: Make an ICE chart for the solution of MgF₂

        MgF₂(s) ⇄ Mg²⁺(aq) + 2 F⁻(aq)

I                           0.36             0

C                           +S             +2S

E                         0.36+S         2S

The solubility product constant is:

Ksp = [Mg²⁺] × [F⁻]² = (0.36+S) × (2S)²

Since S <<< 0.36, 0.36+S ≈ 0.36.

Ksp = 0.36 × 4S² = 8.4 × 10⁻⁸

S = 2.4 × 10⁻⁴ M

Answer: The concentration of the solution is 55.66g[tex]KNO_3[/tex]/100g[tex]H_2O[/tex]

Explanation:

A solution consists of solute and solvent. A solute is defined as the component present in a smaller proportion while the solvent is defined as the component that is present in a larger proportion.

We are given:

Mass of [tex]KNO_3[/tex] = 2.31 g

Mass of water = 4.15 g

To calculate the concentration in g[tex]KNO_3[/tex]/100 g [tex]H_2O[/tex], we apply unitary method:

In 4.15 g of water, the mass of [tex]KNO_3[/tex] present is 2.31 g

So, in 100 g of water, the mass of [tex]KNO_3[/tex] present will be [tex]\frac{2.31}{4.15}\times 100=55.66g[/tex]

Hence, the concentration of the solution is 55.66g[tex]KNO_3[/tex]/100g[tex]H_2O[/tex]

Answer:

Strontium - 38 (atomic #)

Explanation:

An ion with 38 protons, 36 electrons, and 40 electrons is Strontium. Strontium's atomic number is 38.

Answer:

A

Explanation:

In plant and yeast cells pyruvate is converted into carbon dioxide and a type of alcohol called ethanol . This process is called fermentation and yields only two molecules of ATP per glucose molecule broken down.

[tex]CO_2 + H_20[/tex]+ light energy → [tex]O_2[/tex] + sugar chemical equation represents a process that takes place in yeast cells. Hence, option A is correct.

A representation of a chemical reaction using symbols of the elements to indicate the amount of substance, usually in moles, of each reactant and product.

In plant and yeast cells pyruvate is converted into carbon dioxide and a type of alcohol called ethanol. This process is called fermentation and yields only two molecules of ATP per glucose molecule broken down.

Hence, option A is correct.

Learn more about chemical equations here:

https://brainly.com/question/12363199

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Equilibrium shifts to the right.

OPTION A

Answer:

Volume of the reaction vessel is increased - shift to the left

The reaction is cooled down - shift to the right

H2 is added to the system - shift to the right

The pressure of the system is decreased - shift to the left

A catalyst is added to the system - no change

Water is removed from the system - shift to the right

Explanation:

When a constraint such as a change in temperature, pressure or volume is imposed on a reaction system in equilibrium, the equilibrium position will shift in such a way as to annul the constraint.

When the volume of a reaction system is increased, the equilibrium position shifts in the direction in which there is the highest total volume. This is the left hand side.

Since the reaction is exothermic (heat is given out) when the reaction is cooled down, the forward reaction is favoured.

Adding of reactants shifts the equilibrium position to the right hand side hence when H2 is added, the equilibrium position shifts to the right.

Decreasing the pressure shifts the equilibrium position to the direction of higher total volume hence the equilibrium shifts to the left when pressure is decreased.

A catalyst has no effect on the equilibrium position. It increases the rate of forward and reverse reaction to the same extent hence the equilibrium position is unaffected.

Removal of water from the system increases the rate of forward reaction since a product is being removed from the reaction system.

Explanation:

U can use molar ratio of

Li : Li2SO3

2 : 1

so 3.33÷2=1.665 so 1.67 moles

then u can use the

moles = mass ÷ mr

= 12.33÷ 100.08

= 0.123 moles of CuSO3 then use the molar ratio

CuSO3 : Cu

1:1

so 0.123 moles of cu

hope this make sense:)

Explanation:

Science is the pursuit and application of knowledge and understanding of the natural and social world following a systematic methodology based on evidence

Answer:

16974J of energy are required

Explanation:

The energy required is:

* The energy to heat solid water from -15°C to 0°C using:

q = m*S*ΔT

* The energy to convert the solid water to liquid water:

q = dH*m

* The energy required to increase the temperature of liquid water from 0°C to 75°C

q = m*S*ΔT

The first energy is:

q = m*S*ΔT

m = Mass water = 25g

S is specific heat of ice = 2.03J/g°C

ΔT is change in temperature = 0°C - (-15°C) = 15°C

q = 25g*2.03J/g°C*15°C

q = 761.3J

The second energy is:

q = dH*m

m = Mass water = 25g

dH is heat of fusion of water = 80cal/g

q = 80cal/g*25g

q = 2000cal * (4.184J/1cal) = 8368J

The third energy is:

q = m*S*ΔT

m = Mass water = 25g

S is specific heat of water= 4.184J/g°C

ΔT is change in temperature = 75°C-0°C = 75°C

q = 25g*4.184J/g°C*75°C

q = 7845J

The energy is: 7845J + 8368J + 761J =

16974J of energy are required

The question is incomplete, the complete question is:

Write the net ionic equation for the below chemical reaction:

(c): [tex]FeCl_3+3NH_4OH\rightarrow Fe(OH)_3+3NH_4CI[/tex]

Answer: The net ionic equation is [tex]Fe^{3+}(aq)+3OH^{-}(aq)\rightarrow Fe(OH)_3(s)[/tex]

Explanation:

Net ionic equation is defined as the equations in which spectator ions are not included.

Spectator ions are the ones that are present equally on the reactant and product sides. They do not participate in the reaction.

(c):

The balanced molecular equation is:

[tex]FeCl_3(aq)+3NH_4OH(aq)\rightarrow Fe(OH)_3(s)+3NH_4Cl(aq)[/tex]

The complete ionic equation follows:

[tex]Fe^{3+}(aq)+3Cl^-(aq)+3NH_4^+(aq)+3OH^{-}(aq)\rightarrow Fe(OH)_3(s)+3NH_4^+(aq)+3Cl^-(aq)[/tex]

As ammonium and chloride ions are present on both sides of the reaction. Thus, they are considered spectator ions.

The net ionic equation follows:

[tex]Fe^{3+}(aq)+3OH^{-}(aq)\rightarrow Fe(OH)_3(s)[/tex]

Answer:

I assume your talking about carbon when you say 12 so it'd be 12 grams if you are

Explanation:

The molar mass of any substance in grams per mole is numerically equal to the mass of that substance expressed in atomic mass units.

Hope this helps you some