SMK SUNGAI BESAR

SMK SUNGAI BESAR

Thursday, May 14, 2015

BENGKEL KIMIA KERTAS 3

Bengkel kertas 3 telah sempurna dilaksanakan pada ketetapan berikut:

Tarikh : 2 Mei 2015 (Sabtu)
Masa    : 8.00 pagi hingga 12.30 tengahari
Tempat : Dewan Bestari SMK Sungai Besar
Penceramah: Cik Raja Jamaliah bt Raja Saigon, Guru Cemerlang Kimia
Anjuran   : Panitia Kimia SMK Sungai Besar




Saturday, November 2, 2013

NEUTRALISATION-PENEUTRALAN


Neutralisation/ Peneutralan

Ma Va  = 1  ; if monoprotic acid/HCl/ HNO3:           Ma Va  = 1  ; if diprotic acid:H2SO4
Mb Vb                                                                               Mb Vb     2

End point – takat akhir : ………………………………………………………………………………………………………………………
pH indicator at end point/ penunjuka pH pada takat akhir:
pH indicator/ penunjuk pH
Asid
Neutral
Alkali
Phenolfthalein



Methyl orange




  1. Diagram below shows the apparatus set-up for the titration of 25.0 cm3 of 0.1 mol dm-3 sodium hydroxide, NaOH solution with dilute hydrochloric acid, HCl, using phenolphthalein as an indicator.
    Rajah di bawah menunjukkan susunan radas bagi pentitratan antara 25.0 cm3 larutan natrium hidroksida, NaOH 0.1 mol dm-3 dengan asid hidroklorik cair, HCl, menggunakan fenolftalein sebagai penunjuk.
322
(a) Name the type of reaction that occurs in the conical flask.
      Namakan jenis tindak balas yang berlaku dalam kelalang kon itu.

                    …………………………………………………………………………………………………………………………………………….

(b)  Write a balanced chemical equation for the reaction in (a)(i).
       Tulis persamaan kimia yang seimbang bagi tindak balas dalam(a)(i).

………………………………………………………………………………………………………………………………………………

(c)State the colour change of the solution in the conical flask when the end point of titration is reached.
Nyatakan perubahan warna bagi larutan dalam kelalang kon itu apabila takat akhir pentitratan dicapai

………………………………………………………………………………………………………………………………………………

(a)    20.0 cm3 of hydrochloric acid is needed to neutralise completely the sodium hydroxide solution in the conical flask.
Calculate the molarity of the hydrochloric acid.
20.0 cm3 asid hidroklorik diperlukan untuk meneutralkan dengan lengkap larutan natrium hidroksida dalam kelalang kon itu. Hitung kemolaran asid hidroklorik itu.








  1. Table below shows the concentration and volume of two different types of strong acid, X and Y, which are used to neutralise 20.0 cm3 of 0.5 mol dm-3 potassium hydroxide solution.
    Jadual di bawah menunjukkan kepekatan dan isi padu dua jenis asid kuat yang berlainan, X dan Y, yang digunakan untuk meneutralkan 20.0 cm3 larutan kalium hidroksida 0.5 mol dm-3.
323 
Based on the information in Table above, identify acid X and acid Y.
Berdasarkan maklumat dalam Jadual di atas, kenal pasti asid X dan asid Y.















Latihan/ Exercises:

1.      The following equation represents the neutralisation between sodium hydroxide, NaOH and sulphuric acid, H2SO4:                                                                                               
Persamaan berikut mewakili peneutralan antara barium hidroksida, Ba(OH)2 dan asid hidroklorik, HCl:
H2SO4    + 2NaOH à Na2SO4 + 2H2O

20.00 cm3 of 0.1 moldm-3 sodium hydroxide solution was titrated with 0.1 moldm-3 sulphuric acid. What is the final reading of the burrete if the initial reading is 5.00 cm3?
20.00 cm3 larutan natrium hidroksida 0.1 moldm-3 dititratkan dengan 0.1 moldm-3 asid sulfurik. Apakah bacaan akhir buret jika bacaan awalnya ialah 5.00 cm3?

A     10.00 cm3            B                 15.00 cm3            C             20.00 cm3            D            25.00 cm3


2.      The following equation represents the neutralisation between barium hydroxide, Ba(OH)2 and hydrochloric acid, HCl:                                                                               [spm2010]
Persamaan berikut mewakili peneutralan antara barium hidroksida, Ba(OH)2 dan asid hidroklorik, HCl:
Ba(OH)2 + 2HCl à BaCl2 + 2H2O

What is the volume of 0.5 moldm-3 hydrochloric acid needed to neutralized 25 cm3 of 0.1 moldm-3 barium hydroxide?

A     2.5 cm3                B                 5.0 cm3                C             10.0 cm3              D            12.5 cm3

3.      The equation shows the reaction between sulphuriuc acid and sodium hydroxide.
Persamaan menunjukkan tindak balas antara asid sulfurik dan natrium hidroksida.
[spm 2004]
H2SO4    + 2NaOH à Na2SO4 + 2H2O

What is the volume of 1.0 moldm-3 sodium hydroxide which can neutralize 25.0 cm3 of 1.0 moldm-3 sulphuric acid?
Apakah isipadu larutan natrium hidroksida 1.0 moldm-3 yang akan meneutralkan 25.0 cm3 asid sulfurik 1.0 moldm-3?

A     12.5 cm3              B                 25.0 cm3              C             50.0 cm3              D            75.0 cm3

4.      50.0 cm3 of 0.4 mol dm-3 potassium hydroxide solution, KOH, is titrated with sulphuric acid, H2SO4.                                                                                                          [SPM 2008]
What volume of 1.0 mol dm-3  sulphuric acid is needed to neutralise this potassium hydroxide solution?
50.0 cm3 larutan kalium hidroksida, KOH, 0.4 mol dm-3  dititratkan dengan asid sulfurik, H2SO4. Berapakah isi padu asid sulfurik 1.0 mol dm-3  yang diperlukan untuk meneutralkan larutan kalium hidroksida ini?
A     10.0 cm3                   A             20.0 cm3                   A             40.0 cm3                   A             50.0 cm3

5.      A dibase acid, H2J has the concentration of 0.5 mol dm-3.Letter J is not the actual symbol of the element.                                                                                                                  [spm2006]
Satu asid dwibes, H2J mempunyai kepekatan 0.5 mol dm-3.Huruf J bukan simbol sebenar unsur itu.
What is the volume of potassium hydroxide, KOH, 1.0 mol dm-3 that can neutralize 25.0 cm3 of the H2J acid solution?
Berapakah isipadu kalium hidroksida, KOH, 1.0 mol dm-3 yang dapat meneutralkan 25.0 cm3 larutan asid H2J itu?
A     6.25 cm3              B             12.50 cm3            C             25.00 cm3            D            50.00 cm3
6. The following chemical equation shows the reaction between sulphuric acid and sodium   
       hydroxide.
Persamaan kimia berikut menunjukkan tindak balas antara asid sulfurik dengan natrium hidroksida.                                                                                                                             [SPM2011]
H2SO4(aq) + 2NaOH(aq) → Na2SO4(aq) + 2H2O(l)

What is the molarity of sulphuric acid used when 100 cm3 of the acid neutralises 0.04 mol of sodium hydroxide?
Berapakah kemolaran asid sulfurik yang digunakan apabila 100 cm3 asid itu meneutralkan 0.04 mol natrium hidroksida?

A     0.02 mol dm–3    B             0.08 mol dm–3      C             0.20 mol dm–3      D    0.80 mol dm–3

   
7.      The equation shows the reaction between sulphuric acid and potassium hydroxide.
H2SO4  +  2KOH  →  K2SO4  +  2H2O
 
Persamaan di bawah menunjukkan tindakbalas  antara asid sulfurik dan kalium  hidroksida.


What is the volume of 0.1 mol dm-3 potassium hydroxide solution which can neutralise 20.0 cm3 of 0.1 mol dm-3 sulphuric acid?
Berapakah isipadu larutan kalium hidroksida  0.1 mol dm-3 yang diperlukan untuk meneutralkan  20.0 cm3  0.1 mol dm-3 asid sulfurik ?

A    10.00 cm3            B   20.00 cm3      C             40.00 cm3            D            80.00 cm3














1.      Question below is  about the titration between sulphuric acid and sodium hydroxide solution.
Soalan di bawah berkaitan dengan pentitratan antara asid sulfurik dan larutan natrium hidroksida.


Text Box: Several drops of phenolphthalein indicator are added into 25 cm3 of 0.5 mol dm-3 sodium hydroxide solution ia a beaker.
Beberapa titis penunjuk fenoftalin ditambah kepada 25 cm3 larutan natrium hidroksida berkepakatan 0.5 mol dm-3 di dalam bikar.
 






(a)    State the change on the colour of the phenolphthalein in the sodium hydroxide solution at the end point.                                                                                                                     [1M]
Nyatakan perubahan warna fenoftalin dalam larutan natrium hidroksida pada takat akhir.
                                                                                                                                        ........................................................................................................................................
(b)    State the meaning of the end point of titration.                                                         [1M]
Nyatakan maksud bagi takat akhir titratan.

..........................................................................................................................................
(c)    Write a chemical equation to represent the reaction between sulphuric acid and sodium hydroxide solution.                                                                                                            [2M]
Tuliskan persamaan kimia mewakili tindak balas antara asid sulfurik dan larutan natrium hidroksida .

...............................................................................................................................................
(d)    Name the products formed. Namakan hasil yang terbentuk.                                  [1M]

...............................................................................................................................................
(e)    0.25 mol dm-3 of sulphuric acid is needed to completely neutralise the sodium hydroxide solution. Calculate the volume of sulphuric acid.                                                       [3M]
0.25 moldm-3 asid sulfurik diperlukan untuk meneutralkan sepenuhnya larutan natrium hidroksida. Kirakan isipadu asid sulfurik.







(f)     Predict the volume of acid used if the experiment is repeated using 0.25 moldm-3 hydrochloric acid.                                                                                                              [1M]
Anggarkan isipadu asid yang digunakan sekiranya eksperimen diulangi menggunakan 0.25 mol dm-3 asid hidroklorik.

...........................................................................................................................................
(g)    Give two examples of the application of neutralisation in the field of health.     [2M]
Berikan dua contoh aplikasi proses peneutralan dalam bidang kesihatan.

............................................................................................................................................

1.  A student carried out an experiment to determine the end-point for the titration of  25.0 cm3 of 1.0 mol dm-3  sodium hydroxide solution with hydrochloric acid. Phenolphthalein is used as the acid-base indicator. Table 1 shows the three titrations that were conducted and the magnification of the burette readings.
Seorang murid menjalankan eksperimen un tuk menentukan takat akhir pentitratan 25.0 cm3 larutan natrium  hidroksida 1.0 mol dm-3 dengan asid hidroklorik. Fenof talin digunakan sebagai penunjuka asid-bes. Jadual 1 menunjukkan tiga pentitratan yang  telah dijalankan beserta dengan bacaan buret yang telah diperbesarkan.

Titration No.
Bilangan titratan
I
II
III




Initial burette reading

Bacaan awal buret





                                    

  






………………………..











…………………………..










……………………………..



Final burette reading

Bacaan akhir buret

          








    …..……………………


     



     




  ….……………………
              









 …..…………………….
Jadual/ Table 1
(a)      Record the burette readings for the three titrations in the spaces provided in Table 1.
Rekodkan bacaan buret bagi tiga titratan pada ruang yang disediakan dalam Jadual 1.




(b)    Construct a table and record the initial burette reading, final burette reading and the volume of acid used for each titration.
Bina satu jadual dan rekodkan bacaan awal buret, bacaan akhir buret dan isipadu asid yang digunakan dalam setiap titratan.







[3 marks]
(c)    Calculate the molarity of the hydrochloric acid used in the experiment.
Hitungkan kemolaran asid hidroklorik yang digunakan dalam eksperimen ini




[ 3 marks]
(d)  The experiment is repeated by replacing hydrochloric acid 1.0 mol dm-3 with sulphuric acid 1.0 mol dm-3.
Eksperimen diulangi dengan menggantikan asid hidroklorik 1.0 moldm-3 dengan asid sulfurik 1.0 moldm-3.

(i)            Predict the volume of sulphuric acid needed to neutralise the sodium hydroxide  solution.
                        Ramalkan isipadu asid sulfurik yang diperlukan untuk meneutralkan larutan natrium
                        hidroksida.

                      ..............................................................................................................................

(ii)      Explain your answer for (d) (i). Terangkan jawapan anda dalam (d)(i)

                      ……......................................................................................................................

                      ……......................................................................................................................
[3 marks]


(d)    Table 1 shows the results of an experiment to investigate the relationship between the pH values of acids and the strength of acid.
Jadual 1 menunjukkan keputusan eksperimen untuk menyiasat hubungan antara nilai pH asid dengan kekuatan asid.

Solution/ Larutan
pH value/ Nilai pH
Hydrochloric acid, 1.0 mol dm-3
2.0
Ethanoic acid, 1.0 mol dm-3
5.0
Table 1
                 For this experiment, state/ Bagi eksperimen ini, nyatakan
(i)           The manipulated variable/ Pembolehubah yang dimanipulasikan
                        ..........................................................................................................................................
(ii)  The responding variable/ Pembolehubah yang bergerakbalas

                     ……..................................................................................................................................
(iii)The fixed variable/ Pembolehubah yang dimalarkan

                ……..................................................................................................................................
[3 marks]
(e)    State one hypothesis for this experiment.Nyatakan satu hipotesis bagi eksperimen ini.

               …………………………………………………………………….………………………………..………………………………………
……………………………….………………………………………………………………………………………………………………
[3 marks]
(f)     Classify the following substances into substances with pH value less than 7 and pH value more than 7.
Kelaskan bahan-bahan berikut kepada bahan yang mempunyai nilai pH kurang dari 7 dan pH lebih dari 7.
Ethanoic acid                                    Barium hydroxide
                                             Ammonia solution                            Nitric acid





[3 marks]