Question

Supply the missing names or symbols for the elements in the spaces provided: (a) \(\mathrm{N}\) (b) \(\mathrm{K}\) (c) \(\mathrm{Cl}\) (d) Calcium (e) \(\quad\) Phosphorus \(\quad\) (f) \(\quad\) Manganese

Short answer

(a) Nitrogen, (b) Potassium, (c) Chlorine, (d) Ca, (e) P, (f) Mn.

Step-by-step solution

Identify the Element for Symbol 'N'

The chemical symbol 'N' refers to the element Nitrogen, which has the atomic number 7 and is a non-metal gas at room temperature. Fill 'Nitrogen' in the provided space.

Identify the Element for Symbol 'K'

The chemical symbol 'K' stands for Potassium, an alkali metal with the atomic number 19. Fill 'Potassium' in the provided space.

Identify the Element for Symbol 'Cl'

The symbol 'Cl' represents the element Chlorine, which is a halogen with the atomic number 17. Fill 'Chlorine' in the provided space.

Identify the Symbol for Element 'Calcium'

The element Calcium has the chemical symbol 'Ca'. It is an alkaline earth metal with the atomic number 20. Fill 'Ca' in the provided space.

Identify the Symbol for Element 'Phosphorus'

The element Phosphorus has the chemical symbol 'P'. It is a non-metal with the atomic number 15. Fill 'P' in the provided space.

Identify the Symbol for Element 'Manganese'

Manganese is a transition metal with the chemical symbol 'Mn' and atomic number 25. Fill 'Mn' in the provided space.

Key concepts

Chemical Symbols

Chemical symbols are short-hand notations used to represent elements in the periodic table. They allow for easy communication and are universally recognized among scientists and students alike.
Each chemical symbol is typically composed of one or two letters. The first letter is always capitalized, while the second, if present, is lowercase. For example, carbon is represented by 'C', while sodium is 'Na.'

• A capital letter is used first: Example - 'H' for Hydrogen.
• A second lowercase letter may follow if needed: Example - 'He' for Helium.

These symbols often derive from either the English name or the Latin name of the element. For instance, 'Au' represents gold, from the Latin word 'Aurum.' Understanding these symbols is crucial for anyone studying chemistry.

Atomic Number

The atomic number is a fundamental property of an element. It represents the number of protons in the nucleus of an atom of the element.
This number is unique to each element and determines the element's position in the periodic table.
It is displayed above the element's symbol in the periodic table.

• The atomic number defines the identity of an element: Hydrogen has 1 proton, so its atomic number is 1.
• As the atomic number increases, so does the size of the periodic table.

Atomic numbers not only help in identifying an element but also play a critical role in determining chemical behaviors during reactions.

Element Classification

Elements in the periodic table can be classified into different categories based on shared properties. Broadly, elements are grouped as metals, non-metals, or metalloids.
This classification helps us understand their chemical behaviors.

• Metals are typically good conductors of heat and electricity, have high melting points, and are malleable: For example, Iron (Fe).
• Non-metals are usually poor conductors and have lower boiling and melting points: For example, Oxygen (O).
• Metalloids exhibit properties of both metals and non-metals: A common example is Silicon (Si).

Recognizing these classifications can help predict how different elements will interact in reactions.

Non-Metals

Non-metals are a category of elements that usually exhibit properties opposite to metals. These elements can be found on the right side of the periodic table, excluding the noble gases.
Non-metals are essential in forming various compounds necessary for life.

• They are poor conductors of heat and electricity. This makes them good insulators.
• Their states at room temperature vary—some are gases like oxygen, while others are solids like sulfur.

Some well-known non-metals include carbon, nitrogen, and chlorine. They are vital in organic chemistry and biological processes.

Alkali Metals

Alkali metals are a group of elements located in Group 1 of the periodic table. They are highly reactive, especially with water, which means they are rarely found in their pure form in nature.
These metals are known for their shiny appearance and softness.

• They have a single electron in their outermost shell, which they readily lose to form positive ions.
• This group includes elements such as lithium (Li), sodium (Na), and potassium (K).
• Alkali metals have low melting points relative to most other metals.

Their high reactivity plays a significant role in chemical manufacturing processes and various applications in industries.