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  1. Problems
  2. /Structure of the Atom
  3. /Subatomic Particles and Atomic Models

Subatomic Particles and Atomic Models

Chemistry
+ Upload a Problem
More in Structure of the AtomSubatomic Particles and Atomic ModelsElectronic Configuration and ValencyIsotopes and IsobarsLight, Atomic Spectra and the Bohr ModelQuantum Mechanical Model of the Atom
20 problems
Type:
1.
Rubidium has two isotopes, ⁸⁵Rb and ⁸⁷Rb.
High School (11–12) · Isotopes and Isobars, Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
2.
Singly charged ions of boron-10 and boron-11 are accelerated through the same voltage and enter the…
High School (11–12) · Isotopes and Isobars, Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
3.
Find the numbers of protons, neutrons and electrons in ³²₁₆S²⁻, ²⁴₁₂Mg²⁺ and ¹⁹₉F⁻.
High School (11–12) · Isotopes and Isobars, Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Easy
4.
Suppose Thomson's model were true, with the positive charge spread evenly through a gold atom.
High School (11–12) · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
5.
Alpha particles of 6.0 MeV are fired straight at a silver nucleus, with Z = 47 and A = 108.
High School (11–12) · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Hard
6.
The mass number of sodium is 23, and the radius of a sodium atom is about 1.86 × 10⁻¹⁰ m.
High School (11–12) · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
7.
Five oil drops in Millikan's experiment carried the charges 4.806, 12.816, 17.622, 20.826 and…
High School (11–12) · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
8.
In Thomson's tube, the charge to mass ratio of the rays was the same for hydrogen, air and carbon…
High School (11–12) · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Easy
9.
A proton and an electron are each placed in a uniform electric field of 2500 V m⁻¹.
High School (11–12) · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
10.
In a tube filled with helium, some positive rays have a charge to mass ratio of 2.41 × 10⁷ C kg⁻¹.
High School (11–12) · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Easy
11.
Use the energy levels of hydrogen: K -13.6 eV, L -3.4 eV, M -1.51 eV, N -0.85 eV.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
12.
In a hydrogen atom, the L shell has an energy of -3.4 eV and the K shell has -13.6 eV.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Easy
13.
Rutherford's model has electrons that move in circles round the nucleus.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
14.
An atom is about 100 000 times wider than its nucleus.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
15.
In one gold foil experiment, about 1 alpha particle in 8000 bounces back.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
16.
Match each observation of the gold foil experiment with what it tells us.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium
17.
The common atom of hydrogen has a mass of 1 u, and it is neutral.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Easy
18.
The charge of one proton is 1.6 × 10⁻¹⁹ C.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Easy
19.
Name the particle in each case. It is negative and has almost no mass.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Easy
20.
An atom of calcium-40 has 20 electrons. Each electron has a mass of 1/1836 u.
High School (9–10), General · Subatomic Particles and Atomic ModelsStemPy LabStemPy Lab
Medium