A.用碳酸钠溶液处理锅炉水垢:CaSO4(s)+CO⇌CaCO3(s)+SO |
B.湿润的淀粉碘化钾试纸遇氯气变蓝:3Cl2+I-+3H2O=6Cl-+IO+6H+ |
C.铝粉和氧化铁组成的铝热剂用于焊接钢轨:2Al+Fe2O3Al2O3+2Fe |
D.淡黄色的过氧化钠敞口放置变成白色:2Na2O2+2CO2=2Na2CO3+O2;2Na2O2+2H2O=4NaOH+O2↑ |
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