Physics, Chemistry and Biology: Post your doubts here!

[ZMumin]

Guys could anyone explain why The answer is D?

 

[Getsuga juujisho]

which

which question?

question number 37 also can you please reply to me on the "preparing for ICT exams forum?

 

[Gouki_Destruction]

Guys could anyone explain why The answer is D?
View attachment 63335

Bro it is because during electrolysis of aq NaCl , H+ ions discharge at cathode , and Cl- ions discharge at anode , leaving behind Na+ at cathode and OH- at anode. Na is basic , alkaline metal , so gives UI purple color when reacts with OH- ions to form NaOH , while nothing is left an anode now , so no color change there

 

[Gouki_Destruction]

Bro it is because during electrolysis of aq NaCl , H+ ions discharge at cathode , and Cl- ions discharge at anode , leaving behind Na+ at cathode and OH- at anode. Na is basic , alkaline metal , so gives UI purple color , wyl OH is colorless , so naturally would give colorless result .

By OH i mean Oxygen bcz some oxygen molecules also discharge

 

[Hussein Yasir]

dip a glass rod into the solution, if crystals form on the rod, then it has reached crystallisation point, else it still hasn't

Thanks!!

 

[Dtrickster]

U seem confused or is it I who is confused.I think that Na+ is in the solution so it is to be detected from both indicators help me

By OH i mean Oxygen

c

 

[Dtrickster]

View attachment 63049
Can anyone please show me a sample circuit for ci) , I couldnt really understand the question.

In b the answer is a nor gate at c it changed back to an or gate which can be drawn like this without its symbol

 

[Gouki_Destruction]

U seem confused or is it I who is confused.I think that Na+ is in the solution so it is to be detected from both indicators help me

c

How can it b indicated by two indicators ? If we drop some methyl orange for e.g , the color at cathode should change from orange to yellow right ? It would change cz Na++OH-:NaoH , it an alkali , so it would give a positive test for an alkali

 

[Dtrickster]

How can it b indicated by two indicators ? If we drop some methyl orange for e.g , the color at cathode should change from orange to yellow right ? It would change cz Na++OH-:NaoH , it an alkali , so it would give a positive test for an alkali

The colour at the anode should also change because NaOH is formed in both sides(its the solution) and they said in each electrode so I think they are talking about the gases

 

[Gouki_Destruction]

The colour at the anode should also change because NaOH is formed in both sides(its the solution) and they said in each electrode so I think they are talking about the gases

It cant b , cz Cl2 gas is acidic , should have shown red color by UI then .

 

[Dtrickster]

It cant b , cz Cl2 gas is acidic , should have shown red color by UI then .

They made a mistake I think its c

 

[Dtrickster]

what are metalloids ??

Elements with metallic and non metallic properties

 

[Gouki_Destruction]

Wat subs ru giving this year dtrickster ?

 

[Dtrickster]

Wat subs ru giving this year dtrickster ?

Umm math English physics biology chemistry accounts(which I hate) ICT and arabic

 

[Dtrickster]

Do u guys repeat or wat coz u look lyk uv been here 4 years and y r people desperate 4 trophies

 

[Gouki_Destruction]

Umm math English physics biology chemistry accounts(which I hate) ICT and arabic

Im giving Biology , Chemistry , Physics , English , Math and Pakistan Studies . I have given Urdu n Islamic studies . Have u cleared any sub b4 ?

 

[Gouki_Destruction]

Do u guys repeat or wat coz u look lyk uv been here 4 years and y r people desperate 4 trophies

Repeat wat ?

 

[Dtrickster]

Im giving Biology , Chemistry , Physics , English , Math and Pakistan Studies . I have given Urdu n Islamic studies . Have u cleared any sub b4 ?

Nope all sub's 1 shoti don't want to waste time

 

[Dtrickster]

Like u flunk subjects n all

 

[Gouki_Destruction]

Like u flunk subjects n all

No wtf , v come here cz we have fun chatting wd each other .