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What is the difference between a quantum and a photon?

Which of the following have quantized values? Explain your selections. a. the elevation of the treads of a moving escalator b. the elevations at which the doors of an elevator open c. the speed of an automobile

The power of a red laser \((\lambda=630 \mathrm{nm})\) is 1.00 watt (abbreviated \(\mathrm{W}\), where \(1 \mathrm{W}=1 \mathrm{J} / \mathrm{s}\) ). How many photons per second does the laser emit?

Why should hydrogen have the simplest atomic spectrum of all the elements?

Explain the difference between a ground-state \(\mathrm{H}\) atom and an excited-state \(\mathrm{H}\) atom.

Without calculating any wavelength values, predict which of the following electron transitions in the hydrogen atom is associated with radiation having the shortest wavelength. a. from \(n=1\) to \(n=2\) b. from \(n=2\) to \(n=3\) c. from \(n=3\) to \(n=4\) d. from \(n=4\) to \(n=5\)

In the visible portion of the atomic emission spectrum of hydrogen, are there any bright lines due to electron transitions to the \(n=1\) state?

Balmer observed a hydrogen emission line for the transition from \(n=6\) to \(n=2,\) but not for the transition from \(n=7\) to \(n=2 .\) Why?

What is the wavelength of the photons emitted by hydrogen atoms when they undergo transitions from \(n=4\) to \(n=3 ?\) In which region of the electromagnetic spectrum does this radiation occur?

What is the frequency of the photons emitted by hydrogen atoms when they undergo transitions from \(n=5\) to \(n=3 ?\) In which region of the electromagnetic spectrum does this radiation occur?