Final Answer:
a) K
b) Ca
c) Ga
d) C
e) Br
f) Ba
g) Si
h) Au
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Explanation:
Let’s go through each pair one by one — we’re looking for the atom with the LARGER atomic radius.
Remember:
→ As you go DOWN a group (top to bottom), atoms get BIGGER.
→ As you go RIGHT across a period (left to right), atoms get SMALLER.
a) Li or K → K is below Li → K is bigger
✔
b) Ca or Ni → Both in same period, Ca is on the left → Ca is bigger
✔
c) Ga or B → Ga is below B → Ga is bigger
✔
d) O or C → Same period, C is left of O → C is bigger
✔
e) Cl or Br → Br is below Cl → Br is bigger
✔
f) Be or Ba → Ba is way below Be → Ba is bigger
✔
g) Si or S → Same period, Si is left of S → Si is bigger
✔
h) Fe or Au → Au is below Fe (in the same group if you count transition metals) → Au is bigger
✔
So that’s why we picked those answers!
Parent Tip: Review the logic above to help your child master the concept of periodic table worksheet answers key.
