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Chem Studio by Learn4Less

Element 1

Hydrogen (H)

1
H

hydrogen

Nonmetal · s block · group 1, period 1

Electron configuration
1s11s^{1}
Unpaired electrons
1 (paramagnetic)
Valence electrons
1
Molar mass
1.008 g/mol
Electronegativity
2.2
Atomic radius
37 pm
First ionization energy
1312 kJ/mol
Electron affinity
73 kJ/mol released

Course molecules with hydrogen

Practice

Practice hydrogen

Questions from the course about hydrogen. If you’re signed in, your answers count toward your progress.

  1. Question 1Energy levels of hydrogen-like ionsWarm-up

    What is the energy of the electron in the n=5n = 5 level of a hydrogen atom, in J? Include the sign. (RH=2.179×10−18 JR_H = 2.179 \times 10^{-18}\ \mathrm{J})

    J\mathrm{J}

    Scientific notation: type 4.86e-7 or 4.86 x 10^-7.

  2. Question 2Wavelength of a hydrogen-like transitionExam level

    What is the wavelength, in nm, of the light emitted when the electron in a hydrogen atom falls from n=7n = 7 to n=3n = 3? (RH=2.179×10−18 JR_H = 2.179 \times 10^{-18}\ \mathrm{J})

    nm\mathrm{nm}

    Scientific notation: type 4.86e-7 or 4.86 x 10^-7.

  3. Question 3MO bond orderExam level

    Use molecular-orbital theory to find the bond order of HX2X−\ce{H2-}. Give a decimal if needed (e.g. 1.5).

    Scientific notation: type 4.86e-7 or 4.86 x 10^-7.