Educational worksheet for learning the periodic table of elements.

Let’s solve this step by step.

This worksheet is asking you to fill in missing information for each element on the periodic table — like atomic symbol, name, usage, or other details. But since it’s a blank grid with only numbers (atomic numbers) and group labels, we need to figure out what goes in each box based on standard periodic table knowledge.

However, note: The worksheet doesn’t specify *which* detail to fill in for each cell — it just says “fill in the missing information”. Since no specific column headers are given for “symbol”, “name”, etc., and the boxes are empty except for atomic numbers, the most logical interpretation is that you’re supposed to write the element symbol in each box — because that’s the shortest, most common thing students fill in when practicing the periodic table.

Also, looking at the layout:
- Rows = periods (1 to 7)
- Columns = groups (labeled 1 to 18, plus lanthanides/actinides below)
- Each box has an atomic number (e.g., 1, 2, 3... up to 118)

So for each atomic number, we write the correct chemical symbol.

Let’s go row by row, using standard periodic table data.

---

Period 1:
- Atomic #1 → H (Hydrogen)
- Atomic #2 → He (Helium)

Period 2:
- #3 → Li
- #4 → Be
- #5 → B
- #6 → C
- #7 → N
- #8 → O
- #9 → F
- #10 → Ne

Period 3:
- #11 → Na
- #12 → Mg
- #13 → Al
- #14 → Si
- #15 → P
- #16 → S
- #17 → Cl
- #18 → Ar

Period 4:
- #19 → K
- #20 → Ca
- #21 → Sc
- #22 → Ti
- #23 → V
- #24 → Cr
- #25 → Mn
- #26 → Fe
- #27 → Co
- #28 → Ni
- #29 → Cu
- #30 → Zn
- #31 → Ga
- #32 → Ge
- #33 → As
- #34 → Se
- #35 → Br
- #36 → Kr

Period 5:
- #37 → Rb
- #38 → Sr
- #39 → Y
- #40 → Zr
- #41 → Nb
- #42 → Mo
- #43 → Tc
- #44 → Ru
- #45 → Rh
- #46 → Pd
- #47 → Ag
- #48 → Cd
- #49 → In
- #50 → Sn
- #51 → Sb
- #52 → Te
- #53 → I
- #54 → Xe

Period 6:
- #55 → Cs
- #56 → Ba
- #57–71 → Lanthanides (we’ll handle these separately below)
- #72 → Hf
- #73 → Ta
- #74 → W
- #75 → Re
- #76 → Os
- #77 → Ir
- #78 → Pt
- #79 → Au
- #80 → Hg
- #81 → Tl
- #82 → Pb
- #83 → Bi
- #84 → Po
- #85 → At
- #86 → Rn

Period 7:
- #87 → Fr
- #88 → Ra
- #89–103 → Actinides (handle separately)
- #104 → Rf
- #105 → Db
- #106 → Sg
- #107 → Bh
- #108 → Hs
- #109 → Mt
- #110 → Ds
- #111 → Rg
- #112 → Cn
- #113 → Nh
- #114 → Fl
- #115 → Mc
- #116 → Lv
- #117 → Ts
- #118 → Og

Now, the two rows at the bottom:

Lanthanides (Rare Earth Metals):
Atomic numbers 57 to 71:
- 57 → La
- 58 → Ce
- 59 → Pr
- 60 → Nd
- 61 → Pm
- 62 → Sm
- 63 → Eu
- 64 → Gd
- 65 → Tb
- 66 → Dy
- 67 → Ho
- 68 → Er
- 69 → Tm
- 70 → Yb
- 71 → Lu

Actinides:
Atomic numbers 89 to 103:
- 89 → Ac
- 90 → Th
- 91 → Pa
- 92 → U
- 93 → Np
- 94 → Pu
- 95 → Am
- 96 → Cm
- 97 → Bk
- 98 → Cf
- 99 → Es
- 100 → Fm
- 101 → Md
- 102 → No
- 103 → Lr

✔ All symbols verified against standard periodic table.

Final Answer:
The completed worksheet should have the following element symbols filled in each box corresponding to its atomic number:

Row 1: H, He
Row 2: Li, Be, B, C, N, O, F, Ne
Row 3: Na, Mg, Al, Si, P, S, Cl, Ar
Row 4: K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Kr
Row 5: Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Xe
Row 6: Cs, Ba, [La-Lu], Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, Po, At, Rn
Row 7: Fr, Ra, [Ac-Lr], Rf, Db, Sg, Bh, Hs, Mt, Ds, Rg, Cn, Nh, Fl, Mc, Lv, Ts, Og

Lanthanides (bottom row 1): La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu
Actinides (bottom row 2): Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, No, Lr