Periodic Table: Elements and Properties

Part 1:

Name two elements that have the same properties as magnesium (Mg).

Part 2:

Determine the number of protons, electrons, and neutrons present in an atom of potassium (K). Explain how you determined your answer using complete sentences.

Answer:

Two elements that have the same properties as magnesium are calcium and strontium.

The number of protons in potassium, K = 19

The number of electrons in potassium, K = 19

The number of neutrons in potassium, K = 20

What is the Periodic Table?

The Periodic Table is a table that arranges the elements in order of increasing atomic number into vertical columns called groups and horizontal rows called periods. Elements in the same period have the same number of electron shells or energy levels. Elements in the same group have the same number of valence electrons or outermost shell electrons.

Considering the given data:

The elements in group 1 are sodium, potassium, and rubidium.

The elements in group 2 are magnesium, calcium, and strontium.

The elements in group 3 are scandium and yttrium.

The number of protons, electrons, and neutrons present in an atom of potassium (K) is determined by the atomic number and mass number of potassium.

Atomic number = number of protons

Number of proton = number of electrons in a neutral atom

Number of neutrons = mass number - atomic number

The atomic number of potassium = 19

Mass number = 39

Number of neutrons = 39 - 19 = 20

Final answer:

The elements with the same properties as magnesium are calcium and strontium. Potassium has 19 protons, 19 electrons, and 20 neutrons.

Explanation:

The elements with the same properties as magnesium (Mg) are calcium (Ca) and strontium (Sr). All three elements are in the same group, Group 2, of the periodic table, known as the alkaline earth metals. They have similar properties, such as being shiny, silver-white in color, and relatively reactive.

Potassium (K) has 19 protons, 19 electrons, and 20 neutrons. The number of protons is equal to the atomic number, which is 19 for potassium. The number of electrons is also equal to the atomic number in a neutral atom. To find the number of neutrons, subtract the atomic number from the mass number, which is 39 in the case of potassium.

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