Understanding Elements Quiz

10 Questions

What is an element?

A pure substance made of atoms of only one kind

How many elements are included in the periodic table?

118

What is the role of the atomic number in grouping elements in the periodic table?

Specifies the number of protons in the nucleus

Who is recognized as the father of the periodic table?

Dmitri Mendeleev

How do elements exist in nature?

As a pure substance made of atoms of only one kind

What determines the position of an element in the periodic table?

Number of protons

What do elements in the same period of the periodic table have in common?

Same number of energy levels

Which category do alkali metals belong to in the periodic table?

Group 1

What type of bond is formed when atoms share or transfer electrons to enhance stability?

Covalent bond

Which compound is represented by the formula Mg(NO3)2?

Magnesium nitrate (Mg(NO3)2)

Study Notes

The position of an element in the periodic table is determined by the number of protons it has.
A periodic table consists of rows (periods) and columns (groups).
Elements in the same period have the same number of energy levels, while the number of electrons in the outer shell increases as you move from left to right.
Elements in the same group have the same number of energy levels and the same number of electrons in their outer shell.
The periodic table traditionally includes four main groups: Group 1 (alkali metals), Group 2 (alkaline earth metals), transition metals, Group 17 (halogens), and Group 18 (noble gases).
Atoms form molecules by either sharing or transferring electrons to enhance stability.
Molecules can be homonuclear (made up of the same element, like an oxygen molecule) or heteronuclear (made up of different elements, like water).
Molecules can be categorized by the number of atoms they contain: monatomic (one atom, like helium), diatomic (two atoms, like oxygen gas), triatomic (three atoms, like water), tetratomic (four atoms, like phosphorus), pentatomic (five atoms), and hexatomic (six atoms).
Compounds are pure substances formed when at least two different elements combine chemically and have their atoms bonded together.
Compounds have a fixed number of atoms and are represented by a fixed formula.
Elements in a compound are not easily separated by physical and chemical means but can be chemically broken down.
Examples of compounds include potassium carbonate (K2CO3), magnesium nitrate (Mg(NO3)2), copper sulfate (CuSO4), sodium chloride (NaCl), copper sulfide (CuS), and water (H2O).
All compounds are molecules, but not all molecules are compounds.