The periodic table was invented by Russian chemist Dmitri Mendeleev(1834-1907). However, he erroneously thought that the periodic sequence of elements in the table was due to their atomic weight. English physicist Henry Mosley(1887-1915) later proved that the periodicity is due to the number of protons in an atom.
The periodic table is a good starting place for learning about or reviewing the fundamental elements that make up existential matter, in particular, their names, symbols and atomic numbers.
Elements Cs, Fs ,Hg,Ga,Br are liquids or melt at room temperature
Gases other than the noble gases are N, O, F, Cl
Elements with atomic numbers 93-118 are synthetic elements
The remaining elements are solids.
QuizThe coordinates of an element E, in the periodic table is E(p,g). p is the period of the element and g is its group. For example, the coordinate of hydrogen is H(1,1).
1.What elements have the following coordinates:
E(7,7); E(7,14); E(4,11); E(3,1);
2. What element has its atomic number equal to its group number
3. How many elements have symbols similar to the two letters that are used to abbreviate the names of American states.
4. Who discovered the electron.
5. Who discovered the neutron.
6. Who is considered by many scientists as the father of nuclear physics.
7. If the atomic number of an element is 11, how many electrons are in the atom.
8.What is an isotope.
9. How many of the elements in the periodic table have isotopes.
10.What is radioactivity.
11.How many of the elements in the periodic table are radioactive.
12.What are atomic spectral lines?