WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now

If 20 cm\(^3\) of sodium hydroxide was neutralized by 20 cm\(^3\) of 0.01 mol dm\(^3\) tetraoxosulphate(VI)...

Chemistry
WAEC 2020

If 20 cm\(^3\) of sodium hydroxide was neutralized by 20 cm\(^3\) of 0.01 mol dm\(^3\) tetraoxosulphate(VI) acid, what is the concentration of the sodium hydroxide solution?

  • A. 0.010
  • B. 0.020
  • C. 0.100
  • D. 0.150
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post UTME Past Questions Agent
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Correct Answer: Option B
Explanation

2NaOH  +  H\(_2\)SO\(_4\)  →  Na\(_2\)SO\(_4\)  + 2H\(_2\)O

FRom the reaction, N\(_a\) = 1 ;  N\(_b\) = 2

\(\frac{CaVa}{CbVb}\)  = \(\frac{Na}{Nb}\)

\(\frac{{0.01}\times{20}}{{C_b}\times{20}}\)  = \(\frac{1}{2}\)

cross multiply → C\(_b\) = \(\frac{{0.01}\times{20}\times{2}}{{20}\times{1}}\) 

C\(_b\) = 0.02 mol/dm\(^3\)


Report an Error Ask A Question Download App
Post UTME Past Questions Agent
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts

Contributions ({{ comment_count }})

Please wait...

{{ settings.no_comment_msg ? settings.no_comment_msg : 'There are no comments' }}

Quick Questions

Post your Contribution

Please don't post or ask to join a "Group" or "Whatsapp Group" as a comment. It will be deleted. To join or start a group, please click here

{{ quote.posted_by.display_name }}
{{ settings.form_textarea_description }}
 
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Your School's Whatsapp Group - Join Us now
Post UTME Past Questions Agent
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Your School's Whatsapp Group - Join Us now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts