A.化学观念:酸溶液中都含有H+,所以具有相似的化学性质 |
B.科学思维:碱能使无色酚酞溶液变红,能使无色酚酞溶液变红的一定是碱 |
C.科学探究与实践:将火柴梗迅速平放入蜡烛的火焰中约1s后取出,探究火焰哪层温度最高 |
D.科学态度与责任:可燃性气体遇明火易发生爆炸,加油站要严禁烟火 |
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