为了防止I2的挥发,在间接碘量法中必须注意:()。A、加热以加快反应速度B、滴定时应使用碘量瓶且不能剧烈摇动C、反应时溶液温度不能过高D、加入过量的KI
为了防止I2的挥发,在间接碘量法中必须注意:()。
- A、加热以加快反应速度
- B、滴定时应使用碘量瓶且不能剧烈摇动
- C、反应时溶液温度不能过高
- D、加入过量的KI
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阅读程序: Sub p( b () As Integer)For i =1To 4 b(i) = 2(iNext i End Sub Private Sub Command1_Click()Dim a (1 To 4) As Integer a(1)=5 a(2)=6 a(3)=7 a(4)=8 call p (a) For i=1 To 4 Print a(i) Next iEnd Sub运行上面的程序,单击命令按钮,输出结果为。
以下程序的运行结果是( ) #define MAX 10 int a[MAX],i; main() { printf("\n");sub1();sub3(A) ,sub2(),sub3(A) ; } sub2() { int a[MAX],i,max; max=5; for(i=0;i<max;i++)a[i]=i; } sub1() {for(i=0;i<MAX;i++)a[i]=i+i; } sub3(int a[]) { int i; for(i=0;i<MAX,i++)printf("%d",a[i]); printf("\n"); }A.0 2 4 6 8 10 12 14 16 18 0 1 2 3 4B.0 1 2 3 4 0 2 4 6 8 10 12 14 16 18C.0 1 2 3 4 5 6 7 8 9 0 1 2 3 4D.0 2 4 6 8 10 12 14 16 18 0 2 4 6 8 10 12 14 16 18
编写如下事件过程: Private sub sub1 (ByVal x1 As String, y1 As String) Dim xt As String Dim i As Integer i = Len(x1) Do While i>= 1 xt = xt + Mid(x1, i, 1) i=i-1 Loop y1 = xt End Sub Private Sub Form. Click() Dim s1 As String, s2 As String s1= "teacher" sub1 s1, s2 Print s2 End Sub 程序运行后,单击窗体,则窗体上显示的内容是A.rehcaetB.tahreeeC.themeeD.eerthea
有程序如下: Sub subP(b() As Integer) For i=1 To 4 b(i)=2*i Next i End Sub Private Sub Command1_Click() Dim a(1 To 4) As Integer a(1)=5 a(2)=6 a(3)=7 a(4)=8 subP a() For i=1 To 4 Print a(i) Next i End Sub运行上面程序,单击命令按钮,输出结果为______ 。A. 2 4 6 8B.5 2 2 2C.10 12 14 16D.出错
class Super { public int i = 0; public Super(String text) { i = 1; } } public class Sub extends Super { public Sub(String text) { i = 2; } public static void main(String args[]) { Sub sub = new Sub(“Hello”); System.out.println(sub.i); } } What is the result?() A、 0B、 1C、 2D、 Compilation fails.
单选题class Super { public int i = 0; public Super(String text) { i = 1; } } public class Sub extends Super { public Sub(String text) { i = 2; } public static void main(String args[]) { Sub sub = new Sub(“Hello”); System.out.println(sub.i); } } What is the result?()A 0B 1C 2D Compilation fails.
单选题class super ( public int I = 0; public super (string text) ( I = 1 ) ) public class sub extends super ( public sub (string text) ( i= 2 ) public static void main (straing args) ( sub sub = new sub (“Hello”); system.out. PrintIn(sub.i); ) ) What is the result?()A Compilation will fail.B Compilation will succeed and the program will print “0”C Compilation will succeed and the program will print “1”D Compilation will succeed and the program will print “2”
多选题在碘量法中为了减少I2的挥发,常采用的措施有()A使用碘量瓶B溶液酸度控制在PH8C适当加热增加I2的溶解度,减少挥发D加入过量KI