Nabteb Gce Chemistry Practical Free Questions And Answers 2017/2018/2019

Nabteb Gce Chemistry Practical Free Questions And Answers 2017/2018/2019

NABTEB Gce 2017 CHEMICAL SOLUTIONS

1ci... CB=0.22m|dm3
Where CA=? , Na=1 , Nb=2
 VA= 24.60cm3, VB= 25.00Cm3

Using CAVA/CBVB=Na/Nb=CA=CBVB/VA*NA/NB

CA=0.22*25*1/24.6*2
=5.5/49.2
0.11mol|dm3




1cii ....2.20g dissolved in 2.50cm3
Concentration is g|dm3=1000*2.20/250
=2200/250
= 8.80g|dm3

Molar mass of B is m|dm3=conc in g|dm3/molar mass
=8.80.022mol



2ai..if it's not use because it react with gas as thus: 2NH + H2O=(NH4)2SO4
ii...Ammonia is very soluble in water at standard temperature and pressure S.TP due to the reduction of farms hydrogen bonds with matter (NH3.H20)


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2aiii..It to prevent tricking back of gas and mixture of gas with water formed during reaction...
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2b.) By increasing the temperature of liquid in some causes or lower the temperature as the case may be (i.e if needed)

1ci... CB=0.22m|dm3
Where CA=? , Na=1 , Nb=2
 VA= 24.60cm3, VB= 25.00Cm3

Using CAVA/CBVB=Na/Nb=CA=CBVB/VA*NA/NB
CA=0.22*25*1/24.6*2
=5.5/49.2
0.11mol|dm3




1cii ....2.20g dissolved in 2.50cm3
Concentration is g|dm3=1000*2.20/250
=2200/250
= 8.80g|dm3

Molar mass of B is m|dm3=conc in g|dm3/molar mass
=8.80.022mol



2ai..if it's not use because it react with gas as thus: 2NH + H2O=(NH4)2SO4
ii...Ammonia is very soluble in water at standard temperature and pressure S.TP  due to the reduction of farms hydrogen bonds with matter (NH3.H20)


===========≠================

2aiii..It to prevent tricking back of gas and mixture of gas with water formed during reaction...
=====≠=========================

2b.) By increasing the temperature of liquid in some causes or lower the temperature as the case may be (i.e if needed)