Question 9

The atomic number of the mystery element is 6.

The atomic number of an element is defined by the number of protons it contains. In this case, the mystery element has 6 protons, which indicates that its atomic number is 6.

A) 6

This option is correct because the atomic number is determined solely by the number of protons in an atom. Since the mystery element has 6 protons, its atomic number is indeed 6.

B) 12

This option is incorrect as it implies that the element has 12 protons. The atomic number cannot be 12 when the element only has 6 protons, which is a direct contradiction of the definition of atomic number.

C) 18

This option is also incorrect because it suggests that the element has 18 protons. Given that the mystery element has only 6 protons, this choice misrepresents the fundamental characteristic of the element.

D) Not enough information

This option is incorrect as well. The question provides sufficient information to determine the atomic number, specifically noting that the element has 6 protons. Therefore, there is indeed enough information to ascertain the atomic number.

Conclusion

The correct answer is 6 because it accurately reflects the number of protons in the mystery element. All other options fail to represent the atomic number based on the provided information, as they either misstate the number of protons or claim insufficient data.