# Atomic & Quantum Theory

## nodal sphere and angular node in 3d(x²-y²)

Draw angular node and nodal sphere of 3d(x²-y²)

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## Number of electrons in an electron sea

I have no idea where to begin on this problem:

How many electrons are in the electron sea of a 4.84 g sample of potassium metal?

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## calculating wavelength and energy from Atomic spectra

I need helping finding the wavelength distances for H lines and an unknown and the the scale factor. Then calculate the wavelength and energy. I have my lines of H and my unknown mapped out already just not sure how to proceed.

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## Help with calculating number of photons

Here's the problem I need help with: A laser pulse with a wavelength of 532nm contains 3.85 mJ of energy. How many photons are in the laser pulse?

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## Chemistry involving quantum numbers, and wavelength and energy

Hello this is my first time. I am doing work in chemistry class. I have 3 questions I am stuck on.

1. For the element V, how many ground state electrons may have the quantum number n=3 and ml=-1?

I have no idea how to approach this.

2. What is the wavelength in nanometers, of a 7.91 ounce baseball thrown at 99.6 miles per hour?

1oz=28.3g (mass), 1 mile= 1609 meters.

From what I have calculated, it is 6.65x10^-26 nanometers but apparently it is wrong and I do not know why.

3. 0.683 moles of photon was absorbed by a sample of hydrogen atoms. If the wavelength of the photon was 208.5 nanometers, what is the total energy (in kj) absorbed by the sample of hydrogen atoms?

What I used for this was E=hc/(wavelength), figured out the amount of energy in J, converted to kilojoules and multiplied by 0.683. What am I doing wrong?

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## Question is under topic, solid state chemistry and boarders on pontential,kinetic energy newton's law etc

1 A ball of mass 2.5 kg is pushed along a frictionless surface with a constant force of 15 N applied. Calculate the acceleration of the ball. Express your answers in m/s

2 An electron is accelerated in a cathode ray tube and moves at a velocity of 3.0*10^6 km/hour. Calculate the kinetic energy of the electron. You can find the mass of an electron on the Table of Constants in the handouts. Express your answer in units of Joules (J).

3 An apple weighing 100 grams is on a shelf at a height of 180 cm from the floor. A child bumps into the shelf and the apple falls onto a nearby table. The table is at a height of 1 m from the floor. Calculate the change in potential energy of the apple between its initial state (on the shelf) and final state (on the table). The gravitational field on earth is 9.81 m/s

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## The thermite reaction, used to weld rails together in the building of railroads, occurs when iron(III) oxide (Fe2O3) reacts with

The thermite reaction, used to weld rails together in the building of railroads, occurs when iron(III) oxide (Fe_{2}O_{3}) reacts with elemental aluminum to produce aluminum oxide (Al_{2}O_{3}) and elemental iron.

**(a)**Write a balanced equation for this reaction, using any correct set of coefficients. Depict the reaction arrow (

b)Calculate the mass of iron metal (in grams) that can be prepared from 150 grams of aluminum and 250 grams of iron(III) oxide.

c)Write the balanced chemical equation using the lowest possible whole number coefficients.

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## Dalton's Theory Mistakes: Which Ones Was He Wrong With?

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## No one has been able to help me with my question yet? Maybe you can? Please I'd really appreciate it? Chemistry Question

The question is in the photo

But I Have been trying to seek for an answer for hours, however no one is able to help me

Can someone please help me? I'd really appreciate it :(

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## No one has been able to help me with my question yet? Maybe you can? Please I'd really appreciate it? Chemistry Question

Question is in the photo.

I've been trying to ask for help on this question for hours, but no one has seem to be able to help me?

I'd really appreciate it if someone could? :(

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