Which scientist proposed the concept of the quantization of energy levels in an atom?

In the periodic table, the alkali metals are found in which group?

What is the term for a bond formed by the attraction between the positive end of one molecule and the negative end of another molecule?

What type of reaction occurs when two compounds exchange positive ions to form new compounds?

The chemical equation 2Fe + 3CuSO₄ → 3Cu + 2Fe(SO₄)₃ represents a:

What type of reaction involves the breakdown of a compound into two or more simpler substances?

The compound Fe₂O₃ is commonly known as:

What is the balanced chemical equation for the reaction between sulfuric acid (H₂SO₄) and sodium hydroxide (NaOH)?

The balanced chemical equation for the reaction between aluminum (Al) and hydrochloric acid (HCl) is:

In chromatography, what is the purpose of a guard column?