Choose the correct answer
1-The POH of 0.05 M NaOH solution is :
A- 12.5 

B- 12.7  

C- 12.9  

D-13.0   

E- none of them

2-The PH of the H⁺ concentration is 5x10^-4M

A- 3.0  

B- 3.3   

C- 3.5    

D- 3.7   

E- none of them

3-The POH of 0. 2 mole potassium hydroxide solution in 500 ml equal to 

A- 12.4     

B- 12.6   

 C- 12.8   

D-13.0    

E- none of them

4- The summation of the H+ and OH- concentration is equal to: 

A- 1x10⁷   

B- 1X10¹⁰   

C- 1X 10¹⁴  

 D- 1X 10^-24   

E-none of them

5-The concentration of a solution whose PH equal to 10.5 is  

A- 2.5 x 10^-11    

B- 3.1 x 10^-11   

C- 3.5 x 10^-11    

D- 4.0X10^-11  

E- none of them