【单选题】已知25℃时,K a (HF)=3.6×10 -4 , K sp (CaF 2 )=1.46×10 -10 。现向1 L 0.2 mol·L -1 HF溶液 中加入1 L 0.2 mol·L -1 CaCl 2 溶液,则下列说法中,正确的是 ( )
A.
25℃时,0.1 mol·L -1 HF溶液中pH=1
B.
K sp (CaF 2 )随温度和浓度的变化而变化
【单选题】What will the future be like when everybody gets online?
A.
People will have equal access to information.
B.
People don’t have to travel to see the world.
C.
People will be living in two different realities.
D.
People don’t have to communicate face to face.
【单选题】What will the future be like when everybody gets online?
A.
People will be living in two different realities
B.
People will have equal access to information.
C.
People don’t have to travel to see the world.
D.
People don’t have to communicate face to face.
【单选题】军人参加集会、晚会,必须按照规定的时间和顺序入场,按照指定的位置就座,遵守会场秩序,不得( )。散会时,依次退场。
【简答题】以原点O向直线l作垂线,垂足为点H(-2,1),则直线l的方程为______.
【单选题】已知25℃时, K a (HF)=3.6×10 - 4 , K sp (CaF 2 )=1.46×10 - 10 。现向1 L 0.2 mol·L - 1 HF溶液中加入1 L 0.2 mol·L - 1 CaCl 2 溶液,则下列说法中,正确的是
B.
25℃时0.2mol·L - 1 HF溶液中pH=2
C.
K sp (CaF 2 )随温度和浓度的变化而变化
【多选题】When will the future value increase?
A.
The compounded term becomes shorter
B.
The compounded term becomes longer
C.
The compounded interest rate decreases
D.
The compounded interest rate increases