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Chemistry Question 133 – AP-EAMCET 2026

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Identify the incorrect statement from the following

Recall the general chemical properties and trends of alkaline earth metals, including their reactivity with non-metals and acids, and the nature of their oxides and hydrides.

Step 1: Analyze the Question and Options✦ Active

The question asks to identify the incorrect statement regarding alkaline earth metals (Group 2 elements: Be, Mg, Ca, Sr, Ba, Ra).

Step 2: Evaluate Statement 1: Nature of Oxides○ Expand

Statement 1: "Among the oxides of alkaline earth metals, oxide of Be is only amphoteric in nature." Beryllium oxide (BeO) is indeed amphoteric, reacting with both acids and bases. The oxides of other alkaline earth metals (MgO, CaO, SrO, BaO) are basic, with basicity increasing down the group. Thus, this statement is correct.

💡 Teacher's Secret Hint

Remember that Beryllium shows diagonal relationship with Aluminum, which also forms amphoteric oxide.

Step 3: Evaluate Statement 2: Reducing Power○ Expand

Statement 2: "Reducing power of alkaline earth metals is less than those of their corresponding alkali metals." Alkali metals (Group 1) have larger atomic radii and lower ionization energies compared to alkaline earth metals (Group 2) in the same period. This makes alkali metals stronger reducing agents. Thus, this statement is correct.

💡 Teacher's Secret Hint

Stronger reducing agents are those that lose electrons more easily. Lower ionization energy generally correlates with higher reducing power.

Step 4: Evaluate Statement 3: Formation of Hydrides○ Expand

Statement 3: "All alkaline earth metals combine with hydrogen upon heating and form MH2 type of hydrides." While most alkaline earth metals (Mg, Ca, Sr, Ba) react directly with hydrogen upon heating to form MH2 type hydrides, Beryllium (Be) does not react directly with hydrogen to form BeH2. Beryllium hydride is typically prepared from reactions of BeCl2 or organometallic beryllium compounds. Therefore, the statement that *all* alkaline earth metals combine with hydrogen is incorrect.

💡 Teacher's Secret Hint

Beryllium's small size and high charge density lead to a more covalent character in its compounds, unlike the more ionic nature of other alkaline earth metal compounds. This often results in different reaction pathways.

Step 5: Evaluate Statement 4: Reaction with Acids○ Expand

Statement 4: "All alkaline earth metals liberate H2 on reaction with acids." Alkaline earth metals are reactive metals and are higher than hydrogen in the electrochemical series. They react readily with dilute acids to produce hydrogen gas (e.g., Mg+2HCl→MgCl2+H2). Thus, this statement is correct.

Step 6: Identify the Incorrect Statement○ Expand

Based on the evaluation, Statement 3 is the incorrect statement.

💡 Teacher's Secret Hint

Always pay close attention to absolute quantifiers like 'all', 'only', 'never' in statements, as these often highlight potential exceptions.

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