Which of the following lists correctly shows the chemical symbols for the first 18 elements of the periodic table in order?

• A. H, He, Li, Be, B, C, N, O, F, Ne, Na, Mg, Al, Si, S, P, Cl, Ar
• B. H, He, Be, Li, B, C, N, O, F, Ne, Na, Mg, Al, Si, P, S, Cl, Ar
• C. H, He, Li, Be, B, C, N, O, F, Ne, Na, Mg, Al, Si, P, S, Cl, Ar
• D. H, He, Li, Be, B, C, N, O, F, Ne, Mg, Na, Al, Si, P, S, Cl, Ar

Answer: (C)

Verified step by step guidance

1. Recall that the periodic table arranges elements in order of increasing atomic number, starting from hydrogen (H) with atomic number 1 up to argon (Ar) with atomic number 18 for the first 18 elements.
2. List the first 18 elements by their atomic numbers and corresponding symbols: 1-H, 2-He, 3-Li, 4-Be, 5-B, 6-C, 7-N, 8-O, 9-F, 10-Ne, 11-Na, 12-Mg, 13-Al, 14-Si, 15-P, 16-S, 17-Cl, 18-Ar.
3. Compare each given list to this correct sequence to check if the order of symbols matches the increasing atomic number sequence.
4. Identify any discrepancies such as swapped elements or incorrect order, for example, swapping Be and Li or P and S would indicate an incorrect list.
5. Confirm the list that exactly matches the correct order of the first 18 elements by atomic number as shown in step 2.