1) What colour flame do lithium ions burn with? a) Crimson b) Yellow c) Lilac d) Orange-red e) Green 2) What colour flame do Potassium ions burn with? a) Crimson b) Yellow c) Lilac d) Orange-red e) Green 3) What colour flame do Sodium ions burn with? a) Crimson b) Yellow c) Lilac d) Orange-red e) Green 4) What colour flame do Calcium ions burn with? a) Crimson b) Yellow c) Lilac d) Orange-red e) Green 5) What colour flame do Copper ions burn with? a) Crimson b) Yellow c) Lilac d) Orange-red e) Green

排行榜

视觉风格

选项

切换模板

恢复自动保存: