Question

This is the periodic table of the elements. Luis made a table of some of the elements and the charges of their ions from period 4. Element Charge K +2 Ca +2 Cr +2 or +3 Se −2 Br −1 According to information in the periodic table, what mistake did Luis make in his table? The −2 charge for Se is incorrect because Se is in group 17 which has charges of −1 when they form ions. B The +2 charge for K is incorrect because K is in group 1 which has charges of +1 when they form ions. C The +2 charge for Cr is incorrect because Cr is in group 1 which has charges of +1 when they form ions. D The −1 charge for Br is incorrect because Br is in group 1 which has charges of −2 when they form ions.

Answer 1

The mistake in Luis's table is assigning a +2 charge to potassium (K), which is a group 1 element and should have a +1 charge when it forms an ion.

Step-by-step explanation:

The mistake that Luis made in his table of elements and their ion charges is related to the charge of potassium (K).

According to the periodic table, elements in group 1, known as alkali metals, form cations with a 1+ charge, not a 2+ charge.

Therefore, the correct answer is: B. The +2 charge for K is incorrect because K is in group 1 which has charges of +1 when they form ions.

In Luis's table, the mistake is that he listed the charge for Se as -2, when in fact according to the periodic table, Se is in group 17 which has a charge of -1 when it forms ions.