Consider an atom that has an electron in an excited state. The electron falls to a lower energy level. What effect does that have on the electron?
A.The electron releases energy in the form of light.
B.The electron absorbs energy in the form of light.
C.The electron retains its energy without any change.
D.The electron transfers its energy to other electrons.

Answers

Answer 1

Answer:

c it does not change the energy state

Explanation:


Related Questions

One of the nuclides in spent nuclear fuel is U-235, an alpha emitter with a half-life of 703 million years. How long will it take for an amount of U-235 to reach 23.0% of its initial amount

Answers

Answer:

1.49 × 10⁹ years

Explanation:

Step 1: Calculate the rate constant (k) for the nuclear decay of U-235

The decay follows first-order kinetics with a half-life (t1/2) of 703 × 10⁶ years. We can calculate "k" using the following expression.

k = ln2/ t1/2 = ln2 / 703 × 10⁶ y = 9.86 × 10⁻¹⁰ y⁻¹

Step 2: Calculate the time elapsed (t) so that the final amount ([U]) is 23.0% of the initial amount ([U]₀)

For first order kinetics, we will use the following expression.

ln ([U]/[U]₀) = -k × t

ln (0.230[U]₀/[U]₀) = -9.86 × 10⁻¹⁰ y⁻¹ × t

ln 0.230 = -9.86 × 10⁻¹⁰ y⁻¹ × t

t = 1.49 × 10⁹ y

What is the pH of a 1.7 × 10⁻⁴ M HClO₄ solution?

Answers

Ph= -log[h30]

Ph= -log[1.7x10^-4]

pH= 3.77

pH is acidic

What would you use to measure
to measure an amount of solid sodium chloride(NaCI)
crystals to add to a 30 mL solution?
A. Triple Beam Balance that measures to the nearest 0.1 grams.
) B. 10 ml graduated cylinder.
Scale that can weigh up to 250 lbs.
D. Spectrophotometer that measures between 100 and 900 nanometers.

Answers

the answer is a. triple beam balance

Arrange the forms of electromagnetic radiation in order of decreasing energy (from highest energy to lowest energy). You are currently in a ranking module. Turn off browse mode or quick nav, Tab to move, Space or Enter to pick up, Tab to move items between bins, Arrow Keys to change the order of items, Space or Enter to drop.
highest energy lowest energy
radio waves
x rays
gamma rays
infrared
microwaves
ultraviolet
visible

Answers

Answer:

gamma rays > X-rays > ultraviolet radiation > visible light > infrared > radio waves.

Explanation:

Electromagnetic waves are those waves that require no material medium for propagation. They can travel through space and they all move at the speed of light.

Electromagnetic waves are composed of both electric and magnetic fields which are mutually at right angles to each other.

The order of decreasing energy of electromagnetic waves is;

gamma rays > X-rays > ultraviolet radiation > visible light > infrared > radio waves.

write the formula
sodium ion

Answers

Answer:

NA+

Explanation:

NA+

hope help

it's NA+

Write the formula of sodium ion.

[tex]\implies {\blue {\boxed {\boxed {\purple {\sf { {Na}^{ + } }}}}}}[/tex]

[tex]\bold{ \green{ \star{ \orange{Mystique35}}}}⋆[/tex]

Convert the following:
1) 367.5 mg = _______ g
2) 367 mL = _______ L
3) 28.59 in =______ cm
4) 8 0z =_______lb
5) 0.671 mm =_____m

Answers

1: 367.5mg=0.3675g
2: 367mL=0.367L
3: 28.59 in = 72.6186 cm
5:0.671mm=0.000671

Identify each of the following sets of quantum numbers as allowed or not allowed in the hydrogen atom.

a. n=3 , l= 2 , ml =2
b. n=4 , l= 3 , ml =4
c. n=0 , l= 0 , mb =0
d. n=2 , l= 1 , mb =1

Answers

Answer:

See explanation.

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to firstly recall the electron configuration of hydrogen:

[tex]1s^1[/tex]

To realize that the principal quantum number is 1, the angular is 0 as well as the magnetic one; therefore we infer that all the given n's are not allowed, just l=0 is allowed as well as ml=0 yet the rest, are not allowed.

Best regards!

Which state of matter is characterized by having an indefinite shape, but a definite volume?


solid

gas

liquid

Answers

Answer:

liquid is the right answer k

Answer:

liquid

Explanation:

What is the volume of 0.410 moles of co2 at STP​

Answers

Answer: 9.18 Litres

Standard Temperature and Pressure (STP). Think of this as the perfect environment where the Temp. is 0°C or 273 Kelvin and Pressure is always 1 atm. This is only true in STP.

This question uses the Ideal Gas Equation:

PV=nRT

P= 1 atm

V = ??

T = 273 K (always convert to Kelvin unless told otherwise)

n = 0.410 mol

R = 0.0821 L.atm/mol.K

What R constant to use depends on the units of the other values. (look at the attachments) The units cancel out and only Litres is left. You simply multiply the values.

Answer:

9.18 liters .............

heya

A flexible vessel contains 65.8 L of gas at a pressure of 2.07 atm. Under the conditions of constant temperature and constant number of moles of gas, what is the pressure of the gas (in atm) when the volume of the vessel increased by a factor of 16.00

Answers

Answer: Pressure of the gas is 0.129375 atm when the volume of the vessel increased by a factor of 16.00.

Explanation:

The formula for ideal gas equation is as follows.

[tex]PV = Nk_{b}T[/tex]

where,

[tex]k_{b}[/tex] = Boltzmann constant

N = number of moles

That can also be written as:

[tex]\frac{PV}{T} = constant[/tex]

As pressure and volume are inversely proportional to each other. So, if one of the state variable is increased then the other one will decrease or vice-versa.

So, if volume of the vessel increased by a factor of 16.00 then it means pressure is decreased by a factor of 16.00

Therefore, final volume is as follows.

[tex]65.8 L \times 16.00\\= 1052.8 L[/tex]

Now, final pressure is as follows.

[tex]\frac{2.07}{16.00}\\= 0.129375 atm[/tex]

Initially the product of pressure and volume is as follows.

[tex]PV = 2.07 \times 65.8\\= 136.206[/tex]

Hence, if volume of the vessel increased by a factor of 16.00 and pressure is decreased by a factor of 16.00 then its product is as follows.

[tex]PV = 0.129375 \times 1052.8\\= 136.206[/tex]

Here, product of pressure and volume remains the same.

Thus, we can conclude that pressure of the gas is 0.129375 atm when the volume of the vessel increased by a factor of 16.00.

HELP ASAP!! if given the following balanced equation, circle one of the following calculations that shows how to correctly determine the amount of CO2 gas (in moles) that will be produced if you start with 6 moles of calcium carbonate CaCO3

Answers

Answer:

The answer is B.

Explanation:

Write a balanced equation for the combination reaction described, using the smallest possible integer coefficients. When methane (CH4) combines with carbon tetrachloride , dichloromethane (CH2Cl2) is formed.

Answers

Answer:

C H₄ + C Cl₄ = 2 (C H₂ Cl₂)

‎‎‎‎‎‎‎‎‎

Identify the indicated protons in the following molecules as unrelated, homotopic, enantiotopic, or diastereotopic. a) Methyls a & b: _________ b) Ha & Hc: _________

Answers

Answer:

Identify the indicated protons in the following molecules as unrelated, homotopic, enantiotopic, or diastereotopic. a) Methyls a & b: _________ b) Ha & Hc: ________

Explanation:

Homotopic hydrogens:

Consider two hydrogens in the given molecule and replace one by one with a different atom say for example deuterium, then if the two molecules formed by replacing hydrogens are the same then the two hydrogens are called homotopic hydrogens.

After replacing the two hydrogens with a different atom then, enantiomers are formed then, the two hydrogens are called enantiotopic hydrogens.

After replacing the two hydrogens with a different atom then, diastereomers are formed then, the two hydrogens are called diastereotopic hydrogens.

In the methyl group, select two hydrogens and replace one hydrogen atom with a D-atom name the compound.

Again replace another hydrogen atom with D-atom.

Name it.

If both are the same then, the hydrogens are homotopic and they are shown below:

Hence, they are homotopic protons.

One source of aluminum metal is alumina, Al2O3. a. Determine the percentage composition of Al in alumina. b. How many pounds of aluminum can be extracted from 2.0 tons of alumina.?

Answers

Answer:

sorry i cant give the answer but you can gi end check in answer sheet of this becoz i had same question in exam in chemistry so i revised then i checked the answer if you want to check answer go to www.coachscotchemistry.com there you xan find the answer

what is a colloidal with liquid as both dispersed phase and dispersion medium called?​

Answers

Answer:

A colloidal system in which liquid is a dispersed phase and solid is dispersion medium is known as Gel.

Explanation:

What is the specific heat value of brass?

Answers

Answer:

Nhiệt dung riêng của đồng là  

380

J

/

k

g

.

K

Explanation:

0.380 0.092
T4: Specific Heats and Molar Heat Capacities
Substance cp in J/g K cp in cal/g K or Btu/lb F
Aluminum 0.900 0.215
Bismuth 0.123 0.0294
Copper 0.386 0.0923
Brass 0.380 0.092

Complete the following road map for converting volume of A to volume of B for a titration of aqueous solution A with aqueous solution B.

a. multiply by the molarity of B
b. multiply by the moles of B per moles of A
c. divide by the molarity of B
d. multiply by the molarity of A
e. divide by the molarity of A
f. multiply by the moles of A per moles of B

1. volume A (L)
2. moles A
3. moles B
4. volume B (L)

Answers

Answer:

Explanation:

The solution of known concentration is expressed as molarity. Molarity is the mole fraction of solute (i.e. the dissolved substance) per liter of the solution, Molarity is also commonly called molar concentration.

Mathematically;

[tex]\mathtt{Molarity = \dfrac{moles \ of \ solute}{ liters \ of \ solution}}[/tex]

To copy and complete the road map from the given question, we have the following array:

      Volume A (L)

               ↓

d. multiplied by the molarity of A

               ↓

          moles A

               ↓

b. multiplied by the moles of B / moles of A

               ↓

         moles B

               ↓

c. divided by the molarity of B

               ↓

        volume B (L)

You HAVE 1L of 2.0 mol/L HCI. You want to dilute the solution to a concentration of 0.1 mol/L. What volume of the new solution (V2)?

0.05 L

O 20L

0.2 L

Answers

Given:

M₁ = 2.0 mol/L

V₁ = 1 L

M₂ = 0.1 mol/L

Required:

V₂

Solution:

M₁V₁ = M₂V₂

V₂ = M₁V₁ / M₂

V₂ = (2.0 mol/L)(1 L) / (0.1 L)

V₂ = 20 L

Therefore, the volume of the new solution will be 20 L.

#ILoveChemistry

#ILoveYouShaina

M₁V₁ = M₂V₂

V₂ = M₁V₁ / M₂

V₂ = (2.0 mol/L)(1 L) / (0.1 L)

V₂ = 20 L

THE BEST ANSWER IS

O 20L

g What happens to the intensity of the solution's color as the concentration of the solute changes? The intensity of the color directly changes in response to the concentration. The intensity of the color inversely changes in response to the concentration. The intensity of the color always increases in response to any concentration change. The intensity of the color always decreases in response to any concentration change. The intensity of the color does not change in response to any concentration change.

Answers

Answer:

The intensity of the color directly changes in response to the concentration

Explanation:

One of the major indicators of the concentration of a solution is the colour of the solution.

The colour of the solution changes as the concentration of the solution changes. If the solution becomes more concentrated, the colour of the solution becomes deeper. If the solution becomes more dilute, the colour of the solution becomes lighter.

It then follows that, the intensity of the color of a solution directly changes in response to the concentration of the solution.

¿Cómo se divide la tecnología?
de te

Answers

Answer:

còmo supòtànté insígídà pàtàtàk

Hydrogen and chlorine gases react to form HCl. You and a friend are on opposite sides of a long hallway, you with H2 and your friend with Cl2. You both want to form HCl in the middle of the room. Which of the following is true?
a) You should release the H2 first.
b) Your friend should release the Cl2 first.
c) You both should release the gases at the same time.
d) You need to know the length of the room to answer this question.
e) You need to know the temperature to answer this question.

Answers

Answer: It is true that Your friend should release the [tex]Cl_{2}[/tex] first.

Explanation:

The velocity of particles of a gas is inversely proportional to the mass of gas. This means that more is the mass of gas less will be its velocity.

Or, more will be the mass of gas more slowly it will move from one place to another.

The molar mass of chlorine gas is more than the molar mass of hydrogen gas. Therefore, chlorine gas will move slowly.

So, your friend should release the [tex]Cl_{2}[/tex] gas first and then according to the length of room you should release the [tex]H_{2}[/tex] gas.

Thus, we can conclude that it is true that Your friend should release the [tex]Cl_{2}[/tex] first.

HELP ME PLZ AND THANKS I WILL MARK YOU AS BRAINLIEST!!!

Answers

Answer:

i think formula is PV=K?

Explanation:

Match the below mention gas law.

____________ states that the volume of a gas is directly proportional to the temperature of the gas, while pressure and number Of moles are kept constant (V/T = constant). All temperatures must be in kelvins when used in gas law calculations.
__________ states that the volume of the gas varies inversely to the pressure on the gas, while temperature and number of moles are kept constant (PV = constant).
____________ states that the volume of a gas is directly proportional to the number of moles of the gas, while pressure and temperature are kept constant (V/n constant).

1. Boyle's law
2. Charles's law
3. Avogadro's law

Answers

Answer:

Charles's law states that the volume of a gas is directly proportional to the temperature of the gas, while pressure and number Of moles are kept constant (V/T = constant). All temperatures must be in kelvins when used in gas law calculations.

Boyle's law states that the volume of the gas varies inversely to the pressure on the gas, while temperature and number of moles are kept constant (PV = constant).

Avogadro's law states that the volume of a gas is directly proportional to the number of moles of the gas, while pressure and temperature are kept constant (V/n constant).

Explanation:

Charles's law says that at constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases. This is because "temperature" means movement of the particles. So, the greater the movement of the particles (temperature), the greater the volume of the gas. Then, Charles's law indicates that the volume is directly proportional to the temperature of the gas.

So, Charles's law states that the volume of a gas is directly proportional to the temperature of the gas, while pressure and number Of moles are kept constant (V/T = constant). All temperatures must be in kelvins when used in gas law calculations.

As the volume increases, the gas particles (atoms or molecules) take longer to reach the walls of the container and therefore collide with them fewer times per unit of time. This means that the pressure will be lower because it represents the frequency of collisions of the gas against the walls. In this way pressure and volume are related, determining Boyle's law which says:

"The volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure"

So, Boyle's law states that the volume of the gas varies inversely to the pressure on the gas, while temperature and number of moles are kept constant (PV = constant).

Avogadro's Law is a gas law that relates the volume and quantity of gas at constant pressure and temperatures. This law states that the volume of a gas held at constant temperature and pressure is directly proportional to the number of moles of the gas: if the amount of gas increases, the volume will increase, and if the amount of gas decreases, the volume decreases.

Then, Avogadro's law states that the volume of a gas is directly proportional to the number of moles of the gas, while pressure and temperature are kept constant (V/n constant).

Answer:

Boyle's Law: This gas relates pressure and volume at a fixed Temperature.

Charles' Law: This gas law relates the volume of a given mass and its temperature at a fixed pressure.

Avogadro's Law: This gas law relates the volume occupied by an ideal gas and the number of moles present at a fixed temperature and pressure.Avogadro's Law

Ideal Gas Law: This law states that the volume of any gas is directly proportional to the number of moles of the gas and the temperature of the gas and is inversely proportional to the pressure of the gas.

Hey what is your guyses fear, I am terrified of wasp, especially those huge red ones I call red goobers.

Answers

I’m terrified of heights and spiders

what is the maximum number of grams of sodium chloride that you could dissolve in 500 grams of water at 20 C

Answers

Answer:

178.5g of NaCl is the maximum amount that can be dissolved

Explanation:

Solubility is defined as the maximum amount of solute that can be dissolved in aAt 20°C, the solubility of NaCl is 35.7g per 100g of water at 20°C. That means the maximum amount that can be dissolved of NaCl is:

500g water * (35.7g NaCl / 100g water) =

178.5g of NaCl is the maximum amount that can be dissolved

When a liquid is heated the average what? Of energy of its particles will increase

Answers

When a substance is heated, it gains thermal energy. Therefore, its particles move faster and its temperature rises.

Name the following ketone:
A. 2,3,5,6-tetraethyl-4-octanal
B. 2,3,5,6-tetramethyl-4-octanone
C. 2,3,5,6-tetramethyl-4-octaketone

Answers

Answer:

it is b step by step

Explanation:

The naming of this compound is 2,3,5,6 tetramethyl-4-octane.

Hence, option (B) is correct answer.

What is Ketone ?    

A ketone is functional group which contains the carbonyl group that is -C = O. The structure for ketone is R¹ - C = O - R² where and are alkyl group or aryl group.

How to naming a compound ?First we have to find the longest continuous carbon chain. Then identify and start naming the functional groups attached to the chain. Starting the numbering of a compound which is starting at the end nearest a group.

Here we can see that the longest carbon chain is Octane. And the functional group is here ketone so suffix is -one. Now starting the number from the left hand side. We can see that on 2, 3,5,6 positions methyl group is attached in this chain. On 4th position ketone group is attached.

So the naming of the ketone is 2,3,5,6 tetramethyl-4-octane.

Thus, from above conclusion we can say that the naming of this compound is 2,3,5,6 tetramethyl-4-octane.

Hence, option (B) is correct answer.

Learn more about the Ketone function group here: https://brainly.com/question/27425066

#SPJ2

A tank at is filled with of sulfur tetrafluoride gas and of sulfur hexafluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction of each gas. Round each of your answers to significant digits.

Answers

The question is incomplete, the complete question is:

A 7.00 L tank at [tex]21.4^oC[/tex] is filled with 5.43 g of sulfur hexafluoride gas and 14.2 g of sulfur tetrafluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction and partial pressure of each gas. Round each of your answers to significant digits.

Answer: The mole fraction of sulfur hexafluoride is 0.221 and that of sulfur tetrafluoride is 0.779

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass.  The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

For sulfur hexafluoride:

Given mass of sulfur hexafluoride = 5.43 g

Molar mass of sulfur hexafluoride = 146.06 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of sulfur hexafluoride}=\frac{5.43g}{146.06g/mol}=0.0372mol[/tex]

For sulfur tetrafluoride:

Given mass of sulfur tetrafluoride = 14.2 g

Molar mass of sulfur tetrafluoride = 108.07 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of sulfur tetrafluoride }=\frac{14.2g}{108.07g/mol}=0.1314mol[/tex]

Total moles of gas in the tank = [0.0372+ 0.1314] mol = 0.1686 mol

Mole fraction is defined as the moles of a component present in the total moles of a solution. It is given by the equation:

[tex]\chi_A=\frac{n_A}{n_A+n_B}[/tex] .....(2)

where n is the number of moles

Putting values in equation 2, we get:

[tex]\chi_{SF_6}=\frac{0.0372}{0.1686}=0.221[/tex]

[tex]\chi_{SF_4}=\frac{0.1314}{0.1686}=0.779[/tex]

Hence, the mole fraction of sulfur hexafluoride is 0.221 and that of sulfur tetrafluoride is 0.779

Which of the following is the correct Lewis dot structure of c4?

Answers

Answer: B

Explanation:

Bacteria and archaea carry out the process of nitrogen fixation, which reduces atmospheric nitrogen, N2, to the biologically useful form NH3, also called ammonia. The nitrogenase complex consists of two proteins, reductase and nitrogenase, which catalyze the reactions of nitrogen fixation. Match each structural feature or function with the corresponding component of the nitrogenase complex.

a. also called the molybdenum—iron protein, or the MoFe protein
b. transfers electrons from a donor, such as frrredoxin, to the other component.
c. Homodimer
d. Heterotetramer

1. Reductase
2. Nitrogenase

Answers

Answer:

a. Nitrogenase

b. Reductase

c. Reductase

d. Nitrogenase

Explanation:

Reductase is a enzyme which promotes chemical reduction for a substance. It is also known as iron protein as iron is main component in reductase. Nitrogenase are molybdenum because they sulfur as co factor

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Consider the system of equations: Equation 1: -2x + 3y=9 Equation 2 : -8.1 7y = 10 Before adding the equations together, which would not result in the elimination of the variables in this system? Multiply the first equation by 8 and the second equation by 2. O Multiply the first equation by 7 and the second equation by 3. O Multiply the first equation by 4 and the second equation by -1. o Multiply the first equation by 14 and the second equation by 6. X=479Does anyone know this please help quick ! help me please! Is for noww :-((( In a newsvendor setting where the seller faces random demand, if two products have the same critical ratio, then their optimal ordering quantity (i.e., the Newsvendor ordering quantity) will be the same.A. TrueB. 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How fast much an 816kg Volkswagen travel to have the same momentum as (a) a 2650kg Cadillac going 16.0 km/h? (b) a 9080-kg truck also going 16.0 km/hr? Consider the line that passes through the point P(4, - 2) and is parallel to the line - 3x - 4y = 2 Write the point-slope equation of the line. Use exact values. Three packing crates of masses, M1 = 6 kg, M2 = 2 kg and M3 = 8 kg are connected by a light string of negligible mass that passes over the pulley as shown. Masses M1 and M3 lies on a 30o incline plane which slides down the plane. The coefficient of kinetic friction on the incline plane is 0.28. A. Draw a free body diagram of all the forces acting in the masses M1 and M2. B. Determine the tension in the string that connects M2 and M3. active : she bakes injera. PLEASEEE HELPPPPPPP!!!!!!! question is above How fast much an 816kg Volkswagen travel to have the same momentum as (a) a 2650kg Cadillac going 16.0 km/h? (b) a 9080-kg truck also going 16.0 km/hr? 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