# How much heat is absorbed when 52.39 H2O(l) at 100°C and 101.3 kPa is converted to steam at 100°C? (The molar heat of vaporization of water is40.7 k/mol.)2.09 x 1020O 2.31% 10110O 1.18 x 102 103O 1.11% 1021)

## Answers

Answer 1
Answer: 2.09 x 1020 that’s the answer

## Related Questions

Write the reaction of ammonia and water. Label the acid, base, conjugate acid and conjugate base.Is Ammonia a weak or strong base?

### Answers

Explanation :

According to the Bronsted Lowry concept, Bronsted Lowry-acid is a substance that donates one or more hydrogen ion in a reaction and Bronsted Lowry-base is a substance that accepts one or more hydrogen ion in a reaction.

Or we can say that, conjugate acid is proton donor and conjugate base is proton acceptor.

The equilibrium reaction will be,

In this reaction, and are base and acid and and are conjugate acid and conjugate base respectively.

Ammonia is a weak base because it accept proton from the water and gives fewer hydroxide ions.

A student was asked to prepare exactly 250 mL of a 0.500 M aqueous potassium hydroxide solution. What mass of potassium hydroxide (molar mass = 56.10 g/mol) must the student dissolve in the 250 mL of solution? 1. 28.1 g 2. 3.0 g 3. None of these 4. 14.0 g 5. 7.01 g 6. 56.1 g

### Answers

Answer:

Option 5 → 7.01 g

Explanation:

Molarity . volume (L) = Moles

This can help us to determine the moles of KOH that are in the solution.

We convert the volume from mL to L → 250 mL . 1L / 1000mL = 0.250 L

0.5 mol /L . 0.250L = 0.125 moles of KOH

Now, we only have to convert the moles to mass, by the molar mass:

Moles . molar mass = mass →  0.125 mol . 56.1 g/mol = 7.01 g

Answer:

We need 7.01 grams of KOH (option 5)

Explanation:

Step 1: Data given

Volume aqueous KOH solution = 250 mL = 0.250 L

Molarity = 0.500 M

Molar mass of KOH = 56.10 g/mol

Step 2: Calculate moles KOH

Moles KOH = molarity * volume

Moles KOH = 0.500 M * 0.250 L

Moles KOH = 0.125 moles

Step 3: Calculate mass of KOH

Mass KOH = moles KOH * molar mass KOH

Mass KOH = 0.125 moles * 56.10 g/mol

Mass KOH = 7.01 grams

We need 7.01 grams of KOH

Many calculators use photocells to provide their energy. Find the maximum wavelength needed to remove an electron from silver (Φ = 7.59 x 10⁻¹⁹ J). Is silver a good choice for a photocell that uses visible light?

### Answers

Answer:

= 261 nm

Silver is not a good choice.

Explanation:

Where,

h is Plank's constant having value

c is the speed of light having value

is the wavelength of the light

Given that:- Energy =

= 261 nm

Visible range has a spectrum of 380 to 740 nm

So, Silver is not a good choice.

### Final answer:

The maximum wavelength needed to remove an electron from silver is approximately 262 nm. Silver is not a good choice for a photocell that uses visible light.

### Explanation:

To find the maximum wavelength needed to remove an electron from silver, we can use the work function of silver, which is Φ = 4.73 eV. The threshold wavelength for observing the photoelectric effect in silver can be calculated using Equation 6.16, which is λ = hc/Φ. Substituting the given values, we have λ = (1240 eV⋅nm) / (4.73 eV), which gives us a threshold wavelength of approximately 262 nm. Since visible light ranges from 400 to 700 nm, silver is not a good choice for a photocell that uses visible light.

### Learn more about photoelectric effect in silver here:

brainly.com/question/35875610

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Identify when an object has a kinetic energy of zero joules.Question 2 options:

A. as a pendulum swings downward.

B. when the energy has been destroyed.

C. just after a ball it leaves your hand pitching a ball.

D. when an object is no longer in motion.

### Answers

Answer:

D I think

Explanation:

cuz 0 j means there is nothing moving

Answer:

D. when an object is no longer in motion.

Explanation:

Name the physical properties used in seperating kerosene and petrol

### step by step explanation

simple distillation can be used when the temperature difference between the boiling points of two miscible liquid is at least 25°c. the temperature difference between the boiling points of kerosene and petrol is 25c. hence, this mixture can separated using simple distillation.

### answer:

simple distillation

the hydrogen gas generated when calcium metal reacts with water is collected over water at 20 degrees C. The volume of the gas is 641 mL and the pressure is 988mmHg. What is the mass in grams of the hydrogen gas obtained? The vapor pressure of water at 20 degrees C is 17.54 mmHg.

### Answers

The mass of hydrogen gas obtained is 0.068 g of hydrogen gas.

The equation of the reaction is;

Ca(s) +2H2O(l) →Ca(OH)2(aq) + H2(g)

We have to obtain the number of moles of hydrogen gas produced using the information in the question.

P =  988mmHg - 17.54 mmHg = 1.28 atm

V = 641 mL or 0.641 L

T = 20 + 273 = 293 K

n = ?

R = 0.082 atmLK-1mol-1

From;

PV = nRT

n = PV/RT

n = 1.28 atm × 0.641 L/ 0.082 atmLK-1mol-1 × 293 K

n = 0.82/24.026

n = 0.034 moles

Mass of hydrogen =  0.034 moles × 2 g/mol = 0.068 g of hydrogen gas

Learn more: brainly.com/question/1445383

Answer:

There is 0.0677 grams of H2 gas obtained

Explanation:

Step 1: Data given

The total pressure (988 mmHg) is the sum of the pressure of the collected hydrogen + the vapor pressure of water (17.54 mmHg).

ptotal = p(H2)+ p(H2O)

p(H2) = ptotal - pH2O = 988 mmHg - 17.54 mmHg = 970.46 mmHg

Step 2: Calculate moles of H2 gas

Use the ideal gas law to calculate the moles of H2 gas

PV = nRT

n = PV / RT

⇒ with p = pressure of H2 in atm = 970.46 mmHg * (1 atm /760 mmHg) = 1.277 atm

⇒ V = volume of H2 in L = 641 mL x (1 L / 1000 mL) = 0.641 L

⇒ n = the number of moles of H2 = TO BE DETERMINED

⇒ R = the gas constant = 0.08206 L*atm/K*mol

⇒ T = the temperature = 20.0 °C = 293.15 Kelvin

n = (1.277)(0.641) / (0.08206)(298.15) = 0.0335 moles H2

Step 3: Calculate mass of H2

Mass of H2 = moles H2 ¨molar H2

0.0335 moles H2 * 2.02 g/mol H2  = 0.0677g H2

There is 0.0677 grams of H2 gas obtained