Eka-boron is also known as germanium. Eka-aluminum is also known as gallium. Which statement is true?

Eka-boron is also known as germanium. Eka-aluminum is also known as gallium. Which statement is true?

• A. Only the 1st statement is true.
• B. Only the 2nd statement is true.
• C. Both statements are true.
• D. Both statements are false.

Answer: (B)

Mendeleev’s eka- prefix was used to denote an undiscovered element placed one position down from a known element in the same group. Eka-boron would be the element directly below boron, but in the real table that position corresponds to aluminum, not germanium. So eka-boron being germanium is not correct. Eka-aluminum, on the other hand, would be the element directly below aluminum, which is gallium, and that prediction matched what was discovered. Thus the statement about eka-aluminum being gallium is true.

Mendeleev’s eka- prefix was used to denote an undiscovered element placed one position down from a known element in the same group. Eka-boron would be the element directly below boron, but in the real table that position corresponds to aluminum, not germanium. So eka-boron being germanium is not correct. Eka-aluminum, on the other hand, would be the element directly below aluminum, which is gallium, and that prediction matched what was discovered. Thus the statement about eka-aluminum being gallium is true.