① | ② | ③ | ④ | ⑤ | ⑥ | ⑦ | ⑧ | ||
原子半径(10-10m) | 0.74 | 1.60 | 1.52 | 1.10 | 0.99 | 1.86 | 0.75 | 0.82 | |
主要化合价 | 最高价 | — | +2 | +1 | +5 | +7 | +1 | +5 | +3 |
最低价 | -2 | — | — | -3 | -1 | — | -3 | — |
A.元素原子序数④大于⑦ | B.②③号元素不可能处于同一周期 |
C.⑤号元素最高价氧化物对应水化物的酸性最强 | D.⑧号元素是金属元素 |

同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

