26 files changed, 497 insertions, 0 deletions
diff --git a/615/CH2/EX2.1/2_1.sce b/615/CH2/EX2.1/2_1.sce
new file mode 100755
index 000000000..d8528101d
--- /dev/null
+++ b/615/CH2/EX2.1/2_1.sce
@@ -0,0 +1,40 @@
+//acids and bases//
+//example 2.1//
+//(a)//
+N1=1/1000;//normality of HCl//
+a=100;//percentage of ionization//
+C1=N1*a/100;
+printf("The concentration of H+ ion in HCl solution is %fg.ion/lit",C1);
+pH1=-log10(C1);
+printf("\nThe pH of N/1000 HCl solution is %f",pH1);
+N2=1/10000;//normality of NaOH solution//
+C2=N2*a/100;
+C2a=C2/10^-4;
+printf("\nThe concentration of OH- ions in N/10000 NaOH solution is %f*10^-4g.ion/lit",C2a);
+k=10^-14;//dissociation constant of water//
+H2=k/C2;
+H2a=H2/10^-10;
+printf("\nThe H+ concentration in N/10000 NaOH solution is %f*10^-10g.ion/lit",H2a);
+pH2=-log10(H2);
+printf("\nThe pH of the N/10000 solution is %f",pH2);
+N3=1/1000;//normality of NaOH solution//
+C3=N3*a/100;
+C3a=C3/10^-3;
+printf("\nThe concentration of OH- ions in N/1000 NaOH solution is %f*10^-3g.ion/lit",C3a);
+H3=k/C3;
+H3a=H3/10^-11;
+printf("\nThe H+ concentration in N/1000 NaOH solution is %f*10^-11g.ion/lit",H3a);
+pH3=-log10(H3);
+printf("\nThe pH of the N/1000 solution is %f",pH3);
+//(b)//
+N=0.1;//normality of given weak base//
+pH=9;//pH of the base//
+H=10^(-pH);
+Ha=H/10^-9
+printf("\nH+ concentration of the weak base is %f*10^-9g.ion/lit",Ha);
+OH=k/H;
+OHa=OH/10^-5;
+printf("\nOH- concentration of the base is %f*10^-5g.ion/lt",OHa);
+a1=OH/N;
+a1b=a1/10^-4;
+printf("\nDegree of ionization of given weak base is %f*10^-4",a1b);
+\ No newline at end of file
diff --git a/615/CH2/EX2.10/2_10.sce b/615/CH2/EX2.10/2_10.sce
new file mode 100755
index 000000000..2acfad24c
--- /dev/null
+++ b/615/CH2/EX2.10/2_10.sce
@@ -0,0 +1,12 @@
+//acids and bases//
+//example 2.10//
+W=0.092;//weight of Formic acid per litre in grams//
+M=46;//molecular weight of Formic acid//
+N=W/M;
+printf('The normality of Formic acid is %fg.equivalent/lit',N);
+V=1/N;
+K=2.4*10^-4;//Dissociation constant of Formic acid at 25C//
+a=sqrt(K*V);//For weak acids//
+printf('\nDegree of dissociation is %f',a);
+H=a*N;
+printf('\n The H+ concentration of the solution is %fg.ion/lit',H);
+\ No newline at end of file
diff --git a/615/CH2/EX2.11/2_11.sce b/615/CH2/EX2.11/2_11.sce
new file mode 100755
index 000000000..09ce48a27
--- /dev/null
+++ b/615/CH2/EX2.11/2_11.sce
@@ -0,0 +1,15 @@
+//acids and bases//
+//example 2.11//
+disp("In the presence of highly ionised NH4Cl,ammonium hydroxide is practically unionised.Thus all NH4+ ions are obtained from the dissociation of NH4Cl");
+k=2.5*10^-5;//dissociation constant of NH4OH//
+N=1/100;//normality of NH4OH//
+C=N;//since volume of solution is one litre//
+NH=C;
+printf("NH4+ concentration is %fg.ion/lit",NH);
+NHOH=C;
+printf("\nNH4OH concentration is %fg.ion/lit",NHOH);
+OH1=k*NHOH/NH;
+OH=OH1/10^-5;
+printf("\nHydroxyl ion concentration in the solution is %f*10^-5",OH);
+a=OH1/N;
+printf("\nDegree of dissociation of the solution is %f",a);
+\ No newline at end of file
diff --git a/615/CH2/EX2.12/2_12.sce b/615/CH2/EX2.12/2_12.sce
new file mode 100755
index 000000000..63981192d
--- /dev/null
+++ b/615/CH2/EX2.12/2_12.sce
@@ -0,0 +1,18 @@
+
+//acids and bases//
+//example 2.12//
+K=1.7*10^-5;//Dissociation constant of NH4OH//
+N=0.01;//Normality of NH4OH solution//
+V=1/N;
+a=sqrt(K*V);//since a is very small//
+printf('percentage of ionization is %f',a);
+OH=a*N;
+printf('\n concentration of OH- ions before addition of NH4Cl is %fg.ion/lit',OH);
+disp("concentration of hydroxyl ions after adding NH4Cl:");
+disp(" In the presence of highly ionized NH4Cl,ammonium-hydroxide will remain practically unionized.Thus,all NH4+ ions will be obtained from dissociation of NH4Cl");
+NH4=0.05;//concentration of NH4+ in g.ion/lit//
+NH4OH=0.01;//concentration of NH4OH in g.mol/lit//
+OH=K*NH4OH/NH4;
+OH=OH/10^-6;
+printf('\n the concentration of hydroxyl ions after adding NH4Cl is %fmg.ion/lit',OH);
+disp(" A comparision of OH- concentration under two conditions indicate that hydroxyl ion concentration is decreased by addition of ammonium chloride");
+\ No newline at end of file
diff --git a/615/CH2/EX2.13/2_13.sce b/615/CH2/EX2.13/2_13.sce
new file mode 100755
index 000000000..48b582413
--- /dev/null
+++ b/615/CH2/EX2.13/2_13.sce
@@ -0,0 +1,23 @@
+//acids and bases//
+//example 2.13//
+k=1.8*10^-5;//dissociation constant of acetic acid at 18C//
+N=0.25;//normality of acetic acid solution//
+V=1/N;
+a=sqrt(k*V);//formula of degree of dissociation for weak acids//
+a1=a/10^-3;
+printf("Degree of dissociation of acetic acid is %f*10^-3",a1);
+H=N*a;
+H1=H/10^-3;
+printf("\nH+ concentration of the solution is %f*10^-3g.ion/litre",H1);
+N2=0.25//normality os sodium acetate added//
+printf("\nIn presence of completely dissociated sodium acetate,acetic acid will be practically unionisad.Thus,all the acetate ions are obtained from dissociation of sodium acetate.");
+CH3COO=N2;
+printf("\nConcentration of CH3COO- is %fg.ion/litre",CH3COO);
+CH3COOH=N2;
+printf("\nConcentration of CH3COOH is %fg.ions/lit",CH3COOH);
+H2=k*CH3COOH/CH3COO;
+H3=H2/10^-5;
+printf("\nH+ ion concentration after adding sodium acetate is %f*10^-5",H3);
+a2=H2/N2;
+a3=a2/10^-5;
+printf("\nDegree of dissociation after adding sodium acetate is %f*10^-5",a3);
+\ No newline at end of file
diff --git a/615/CH2/EX2.14/2_14.sce b/615/CH2/EX2.14/2_14.sce
new file mode 100755
index 000000000..c3b1af2db
--- /dev/null
+++ b/615/CH2/EX2.14/2_14.sce
@@ -0,0 +1,11 @@
+//acids and bases//
+//example 2.14//
+C1=0.06;//concentration od acetic acid in g.mol/lit//
+C2=0.04;//concentration of sodium acetate in g.mol/li//
+disp("Due to the fact sodium acetate being completely dissociated avd acetic acid in the presence of former,the acetate ions are mainly obtained from the former");
+printf("the concentration of acetate ions are %fg.ion/lit",C2);
+K=1.8*10^-5;//dissociation constant of acetic acid//
+H=K*C1/C2;
+printf("\nthe H+ concentration of the solution is %fg.ion/lit",H);
+pH=-log10(H);
+printf("\nThe pH of solution is %f",pH);
+\ No newline at end of file
diff --git a/615/CH2/EX2.15/2_15.sce b/615/CH2/EX2.15/2_15.sce
new file mode 100755
index 000000000..a3453f692
--- /dev/null
+++ b/615/CH2/EX2.15/2_15.sce
@@ -0,0 +1,7 @@
+//acids and bases//
+//example 2.15//
+M1=0.2;//molarity of acetic acid//
+M2=0.2;//molarity of sodium acetate//
+K=1.8*10^-5;
+pH=-log10(K)+log10(M2/M1);//by using Henderson's equation//
+printf("The pH value of buffer solution is %f",pH);
+\ No newline at end of file
diff --git a/615/CH2/EX2.16/2_16.sce b/615/CH2/EX2.16/2_16.sce
new file mode 100755
index 000000000..236f6c595
--- /dev/null
+++ b/615/CH2/EX2.16/2_16.sce
@@ -0,0 +1,16 @@
+//acids and bases//
+//example 2.16//
+N=1/100;//normality of acetic acid//
+V=1/N;
+k=1.8*10^-5;//dissociation constant of acetic acid//
+a=sqrt(k*V);//formula of degree of dissociation for weak acids//
+H=a*N;
+H=H/10^-4;
+printf("H+ concentration of the solution is %f*10^-4",H);
+n=0.01;//sodium acetate added in moles to one litre of acetic acid solution//
+CH3COO=n;
+printf("\nCH3COO- concentration is %fg.ion/lit",CH3COO);
+CH3COOH=n;
+printf("\nCH3COOH concentration is %fg.ion/lit",CH3COOH);
+H1=k*CH3COOH/CH3COO;
+printf("\nH+ ion concentration in the solution after adding the sodium acetate is %fg.ions/litre",H1);
+\ No newline at end of file
diff --git a/615/CH2/EX2.17/2_17.sce b/615/CH2/EX2.17/2_17.sce
new file mode 100755
index 000000000..027816965
--- /dev/null
+++ b/615/CH2/EX2.17/2_17.sce
@@ -0,0 +1,15 @@
+//acids and bases//
+//example 2.17//
+V=10;//volume of water in litres//
+N1=0.10;//moles of HCN added in solution//
+N2=0.10;//moles of NaCN added in solution//
+K=7.2*10^-10;//dissociation constant of HCN//
+CN=0.1;//CN- concentration//
+HCN=0.1;//HCN concentration//
+H1=K*HCN/CN;
+H=H1/10^-10;
+k=1*10^-14;//ionization constant of water//
+printf("H+ concentration in the solution is %f*10^-10",H);
+OH=k/H1;
+OH=OH/10^-5;
+printf("\nOH- concentration in the solution is %f*10^-5",OH);
+\ No newline at end of file
diff --git a/615/CH2/EX2.18/2_18.sce b/615/CH2/EX2.18/2_18.sce
new file mode 100755
index 000000000..4ddbe74be
--- /dev/null
+++ b/615/CH2/EX2.18/2_18.sce
@@ -0,0 +1,8 @@
+//acids and bases//
+//example 2.18//
+K=1.7*10^-5;//dissociation constant of acid//
+pH=3.77//pH value of buffer solution//
+M=pH+log10(K);
+N=10^M;//ratio of salt to acid//
+L=1/N
+printf("The ratio of salt to acid in buffer is %f",L);
+\ No newline at end of file
diff --git a/615/CH2/EX2.19/2_19.sce b/615/CH2/EX2.19/2_19.sce
new file mode 100755
index 000000000..6cef02b01
--- /dev/null
+++ b/615/CH2/EX2.19/2_19.sce
@@ -0,0 +1,13 @@
+//acids and bases//
+//example 2.19//
+k=1.8*10^-5;//dissociation constant of acetic acid//
+M=0.01;//molarity of acetic acid//
+N=M*1;//normality of acetic acid//
+V=1/N;
+a=sqrt(k*V)//degree of dissociation for weak acids//
+printf("degree of dissociation of solution is %f",a);
+H1=a/V;
+H=H1/10^-4;
+printf("\nH+ concentration in solution is %f*10^-4g.ion/lit",H);
+pH=-log10(H1);
+printf("\npH of the solution is %f",pH);
+\ No newline at end of file
diff --git a/615/CH2/EX2.2/2_2.sce b/615/CH2/EX2.2/2_2.sce
new file mode 100755
index 000000000..9a1d75266
--- /dev/null
+++ b/615/CH2/EX2.2/2_2.sce
@@ -0,0 +1,70 @@
+//acids and bases//
+//example 2.2//
+//(a)//
+N=0.002;//normality of acetic acid solution//
+a=2.3;//percentage of ionization//
+H=N*a/100;//concentration of H+ ion//
+printf('the concentration of H+ ions is %fg.ion/lit',H);
+pH=-log10(H);
+printf('\n pH value of acid solution is %f',pH);
+//(b)(i)//
+N1=0.01;//normality of acetic acid solution//
+a1=60;//percentage of ionization//
+H1=N1*a1/100;//concentration of H+ ion//
+printf('\nthe concentration of H+ ions is %fg.ion/lit',H1);
+pH1=-log10(H1);
+printf('\n pH value of acid solution is %f',pH1);
+//(b)(ii)//
+N2=0.1;//normality of acetic acid solution//
+a2=1.8;//percentage of ionization//
+H2=N2*a2/100;//concentration of H+ ion//
+printf('\nthe concentration of H+ ions is %fg.ion/lit',H2);
+pH2=-log10(H2);
+printf('\n pH value of acid solution is %f',pH2);
+//(b)(iii)//
+N3=0.04;//normality of HNO3//
+a3=100;//percentage of ionization//
+H3=N3*a3/100;
+printf("\nthe concentration of H+ ions is %fg.ion/lit",H3);
+pH3=-log10(H3);
+printf("\n the pH of 0.04NHNO3 solution is %f",pH3);
+N4=0.0001;//normality of Hcl//
+a4=100;//percentage of ionization//
+H4=N4*a4/100;
+printf("\nthe concentration of H+ ions is %fg.ion/lit",H4);
+pH4=-log10(H4);
+printf("\n the pH of 0.0001NHcl solution is %f",pH4);
+N5=1;//normality of Hcl//
+a5=100;//percentage of ionization//
+H5=N5*a5/100;
+printf("\nthe concentration of H+ ions is %fg.ion/lit",H5);
+pH5=-log10(H5);
+printf("\n the pH of 1NHcl solution is %f",pH5);
+N6=0.1;//normality of HNO3//
+a6=100;//percentage of ionization//
+OH6=N6*a6/100;
+printf("\nthe concentration of OH- ions is %fg.ion/lit",OH6);
+Kw=10^-14;
+H6=Kw/OH6;
+pH6=-log10(H6);
+printf("\n the pH of 0.1N NaOH solution is %f",pH6);
+N7=0.001;//normality of NaOH//
+a7=100;//percentage of ionization//
+OH7=N7*a7/100;
+printf("\nthe concentration of OH- ions is %fg.ion/lit",OH7);
+Kw=10^-14;
+H7=Kw/OH7;
+pH7=-log10(H7);
+printf("\n the pH of 0.01NaOH solution is %f",pH7);
+//(b)(iv)//
+W=4;//weight of NaOH dissolved in water in grams//
+EW=40;//equivalent weight weight of NaOH//
+N8=W/EW;
+printf("\nnormality of NaOH is %fN",N8);
+a8=100;//percentage of ionization//
+OH8=N8*a8/100;
+printf("\nthe concentration of OH- ions is %fg.ion/lit",OH8);
+Kw=10^-14;
+H8=Kw/OH8;
+pH8=-log10(H8);
+printf("\n the pH of NaOH solution is %f",pH8);
+\ No newline at end of file
diff --git a/615/CH2/EX2.20/2_20.sce b/615/CH2/EX2.20/2_20.sce
new file mode 100755
index 000000000..d694020ef
--- /dev/null
+++ b/615/CH2/EX2.20/2_20.sce
@@ -0,0 +1,19 @@
+//acids and bases//
+//example 2.20//
+N1=0.2//concentration of acetic acid in g.molecule/lit//
+N2=0.25//concentration of sodium acetate in g.molecule/lit//
+K=1.8*10^-5//ionization constant of acetic acid at room temparature//
+pH1=-log10(K)+log10(N2/N1);
+printf("pH value of the solution before adding HCl is %f",pH1);
+N=1//normality of HCl added//
+V=0.5*10^-3//amount of HCl added in lit//
+M=N*V
+printf("\nThe amount of HCl added in moles is %f",M);
+printf("\nassuming HCl to be completely ionized,the amount of H+ ions added will be %f mole",M);
+printf("\n due to addition of H+ ions the amount of acetic acid will increase and that of salt will correspondingly decrease by %f moles",M);
+C1=N1+M//concentration of CH3COOH in moles/lit//
+C2=N2-M//concentration of CH3COONa in moles/lit//
+pH2=-log10(K)+log10(C2/C1);
+printf("\nThe pH of the solution after adding HCl is %f",pH2);
+pH=pH1-pH2;
+printf("\nThe change of pH is %f",pH);
+\ No newline at end of file
diff --git a/615/CH2/EX2.21/2_21.sce b/615/CH2/EX2.21/2_21.sce
new file mode 100755
index 000000000..a6e09d5e0
--- /dev/null
+++ b/615/CH2/EX2.21/2_21.sce
@@ -0,0 +1,16 @@
+//acids and bases//
+//example 2.21//
+K=18*10^-6;//dissociation constant of NH4OH//
+N1=0.1;//normality of NH4OH solution//
+V=1/N1;
+a=sqrt(K*V)//since a is very small//
+printf("degree of dissociation is %f",a);
+OH=a/V;
+printf("\nThe concentration of hydroxyl ion before adding of NH4Cl is %fg.ion/lit",OH);
+W=2//weight of added NH4Cl in grams//
+M=53//molecular weight of NH4Cl//
+C=W/M;
+printf("\nThe concentration of NH4+ ions is %fg.mol/lit",C);
+C1=0.1;//concentration of NH4OH in g.mol/lit//
+OH2=K*C1/C;
+printf("\nThe concentration of hydroxyl ion after adding 2g of NH4Cl is %fg.ion/lit",OH2);
diff --git a/615/CH2/EX2.22/2_22.sce b/615/CH2/EX2.22/2_22.sce
new file mode 100755
index 000000000..511fe4f2d
--- /dev/null
+++ b/615/CH2/EX2.22/2_22.sce
@@ -0,0 +1,21 @@
+//acids and bases//
+//example 2.22//
+ly=11.92;//equivalent conductvity of 0.02acetic acid solution in mho at 20C//
+lih=360;//the equivalent ionic conductance of an infinite dillution of hydrogen ion in mho//
+lic=40;//of acetate ion//
+li=lih+lic;//of acetic acid//
+a=ly/li;//degree of dissociation//
+N=0.02;//normality of acetic acid//
+V=1/N;
+K=(a^2)/V;
+Ka=K/10^-6;
+printf("Dissociation constant of acetic acid is %f*10^-6",Ka);
+W=82;//mol.wt of CH3COONa//
+M=8.2//amount of sodium acetate added in g per litre solution//
+printf("\nIn the presence of sodium acetate,all the acetate ions are obtained from sodium acetate only");
+CH3COO=M/W;
+printf("\nCH3COO- ion concentration is %fg.ion/lit",CH3COO);
+printf("\nCH3COOH concentration is %fg.mol/lit",N);
+H=K*N/CH3COO;
+pH=-log10(K*N/CH3COO);
+printf("\npH of the solution is %f",pH);
diff --git a/615/CH2/EX2.23/2_23.sce b/615/CH2/EX2.23/2_23.sce
new file mode 100755
index 000000000..be9254ba8
--- /dev/null
+++ b/615/CH2/EX2.23/2_23.sce
@@ -0,0 +1,9 @@
+//acids and bases//
+//example 2.23//
+OH=0.0025;//OH- concentration//
+K=1*10^-14//water ionization constant//
+H=K/OH;
+H=H/10^-12;
+printf("The concentration of H+ ions is %f*10^-12M",H);
+printf("\nThe concentration of OH- ions is %fM",OH);
+printf("\nAs concentration of H+ is lesser than the concentration of OH- the cleaning solution will be basic in nature");
+\ No newline at end of file
diff --git a/615/CH2/EX2.24/2_24.sce b/615/CH2/EX2.24/2_24.sce
new file mode 100755
index 000000000..b3385cc5c
--- /dev/null
+++ b/615/CH2/EX2.24/2_24.sce
@@ -0,0 +1,10 @@
+//acids and bases//
+//example 2.24//
+pH=7.3;//pH value of human blood//
+H=10^-pH;
+H1=H/10^-6
+printf("H+ concentration of human blood is %f*10^-6M",H1);
+k=1*10^-14;//water ionization constant//
+OH=k/H;
+OH=OH/10^-6;
+printf("\nOH- concentration of human blood is %f*10^-6M",OH);
+\ No newline at end of file
diff --git a/615/CH2/EX2.25/2_25.sce b/615/CH2/EX2.25/2_25.sce
new file mode 100755
index 000000000..c49741285
--- /dev/null
+++ b/615/CH2/EX2.25/2_25.sce
@@ -0,0 +1,16 @@
+//acids and bases//
+//example 2.25//
+N1=0.2;//normality of HCl//
+V1=25;//volume of HCl in ml//
+M2=0.25;//molarity of NaOH//
+N2=M2*1;//normality of NaOH//
+V2=50;//volume of NaOH in ml//
+V=V1+V2;//volume of resulting solution//
+N=(N2*V2-N1*V1)/V;//normality of resulting solution//
+printf("Concentration of OH- per litre in the mixure will be %fM",N);
+K=1*10^-14;//ionization constant of water//
+H=K/N;
+H1=H/10^-13;
+printf("\nH+ concentration of the solution is %f*10^-13M",H1);
+pH=-log10(H);
+printf("\npH of the mixure will be %f",pH)
+\ No newline at end of file
diff --git a/615/CH2/EX2.26/2_26.sce b/615/CH2/EX2.26/2_26.sce
new file mode 100755
index 000000000..aead534ba
--- /dev/null
+++ b/615/CH2/EX2.26/2_26.sce
@@ -0,0 +1,18 @@
+//acids and bases//
+//example 2.26//
+S=0.2;//salt concentration//
+A=0.2;//acid concentration//
+k=1.8*10^-5;//dissociation constant of acetic acid//
+pH=-log10(k)+log10(S/A);
+printf("pH of the buffer solution before adding HCl is %f",pH);
+v=1*10^-3;//amount of HCl added in lit//
+M=1;//molarity of HCl added//
+n=v*M;//no of moles of HCl added per litre//
+A1=A+n;
+printf("\nAcetic acid concentration after adding HCl will be %fM",A1);
+S1=S-n;
+printf("\nAcetate concentration after adding HCl will be %fM",S1);
+pH2=-log10(k)+log10(S1/A1);
+printf("\npH of the buffer solution after adding HCl is %f",pH2);
+p=pH-pH2;
+printf("\nChange in pH is %f",p);
+\ No newline at end of file
diff --git a/615/CH2/EX2.3/2_3.sce b/615/CH2/EX2.3/2_3.sce
new file mode 100755
index 000000000..54c739933
--- /dev/null
+++ b/615/CH2/EX2.3/2_3.sce
@@ -0,0 +1,25 @@
+//acida and bases//
+//example 2.3//
+//(a)//
+N1=0.1;//normality of acetic acid//
+a1=1.3;//percentage of ionization//
+H1=N1*a1/100;
+printf('the hydrogen ion concentration of solution is %fg.ion/lit',H1);
+//(b)//
+M1=10^-8;//molarity of hcl solution//
+a=100;//percentage of ionization//
+H=M1*a/100;
+
+pH=-log10(H);
+printf('\nthe pH of the Hcl solution is %f',pH);
+disp("Theoretically the pH should be 8,however,the value will be close to 7 because H+ ions of water also plays a role");
+//(c)//
+N2=0.05;//normality of Hcl//
+a2=100;//percentage of ionization//
+pH2=-log10(N2*a2/100);
+printf('\nthe pH of 0.05 Hcl solution is %f',pH2);
+M3=0.05;//molarity os H2SO4//
+N3=M3*2;//normality//
+a3=100;//percentage of ionization//
+pH3=-log10(N3*a3/100);
+printf('\n the pH of 0.05M H2SO4 solution is %f',pH3);
diff --git a/615/CH2/EX2.4/2_4.sce b/615/CH2/EX2.4/2_4.sce
new file mode 100755
index 000000000..25189219b
--- /dev/null
+++ b/615/CH2/EX2.4/2_4.sce
@@ -0,0 +1,37 @@
+//acids and bases//
+//example 2.4//
+H1=0.005;//H+ ion concentration of solution in g.ion/lit//
+pH1=-log10(H1);
+printf("The pH value of solution whose H+ ion concentration is 0.005g.ion/lit is %f",pH1);
+H2=3*10^-4;//H+ concentration of the solution//
+pH2=-log10(H2);
+printf("\nThe pH of a solution in which H+ is 3*10^-4 is %f",pH2);
+pOH2=14-pH2;
+printf("\npOH of the solution is %f",pOH2);
+k=10^-14;//dissociation constant of water//
+OH2=k/H2;
+OH2a=OH2/10^-11;
+printf("\nOH- concentration for a solution is %f*10^-11M",OH2a);
+OH3=0.1//hydroxyl concentration of a solution//
+H3=k/OH3;
+pH3=-log10(H3);
+printf("\npH of the solution whose hydroxyl concentration is N/10g.ion/lit is %f",pH3);
+k4=1.8*10^-5//dissociation constant of acetic acid at 180C//
+N4=0.1;//normality of acetic acid//
+V4=1/N4;
+a4=sqrt(k4*V4);//formula for degree of dissociation//
+H4=N4*a4;//H+ ion concentration//
+pH4=-log10(H4);
+printf("\npH of 0.1N acetic acid solution is %f",pH4);
+N5=0.01;//normality of acetic acid//
+V5=1/N5;
+a5=sqrt(k4*V5);//formula for degree of dissociation//
+H5=N5*a5;//H+ ion concentration//
+pH5=-log10(H5);
+printf("\npH of 0.01N acetic acid solution is %f",pH5);
+N6=0.001;//normality of acetic acid//
+V6=1/N6;
+a6=sqrt(k4*V6);//formula for degree of dissociation//
+H6=N6*a6;//H+ ion concentration//
+pH6=-log10(H6);
+printf("\npH of 0.001N acetic acid solution is %f",pH6);
+\ No newline at end of file
diff --git a/615/CH2/EX2.5/2_5.sce b/615/CH2/EX2.5/2_5.sce
new file mode 100755
index 000000000..f69c9a3a9
--- /dev/null
+++ b/615/CH2/EX2.5/2_5.sce
@@ -0,0 +1,24 @@
+//acids and bases//
+//example 2.5//
+K1=10^-8;//dissociation constant of weak mono basic acid//
+N1=0.01;//normality of the acid//
+V1=1/N1;
+a1=sqrt(K1*V1);//degree of dissociation for weak acids//
+H1=N1*a1;//H+ concentration of the solution//
+pH1=-log10(H1);
+printf("pH value of 0.01N solution of a weak mono basic acid is %f",pH1);
+a2=4/100;//percentage of dissociation of acid at 20C//
+N2=0.1;//normality of acid//
+V2=1/N2;
+K2=(a2^2)/V2;
+K2a=K2/10^-4;
+printf("\nThe dissociation constant of the acid is %f*10^-4",K2a);
+N3=0.1;//normality of HCl//
+pH3=-log10(N3);
+printf("\nThe pH of the 0.1N HCl solution is %f",pH3);
+N4=1/50;//normality of HCl//
+pH4=-log10(N4);
+printf("\nThe pH of the 1/50N HCl solution is %f",pH4);
+N5=0.01;//normality of H2SO4//
+pH5=-log10(N5);
+printf("\nThe pH of the 0.01N H2SO4 solution is %f",pH5);
+\ No newline at end of file
diff --git a/615/CH2/EX2.6/2_6.sce b/615/CH2/EX2.6/2_6.sce
new file mode 100755
index 000000000..8099b8f2e
--- /dev/null
+++ b/615/CH2/EX2.6/2_6.sce
@@ -0,0 +1,15 @@
+//acids and bases//
+//example 2.6//
+V1=50;//volume of Hcl in ml//
+V2=30;//volume of NaOH in ml//
+N1=1;//normality of Hcl//
+N2=1;//nomality of NaOH//
+V=V1+V2;//total volume of mixure of solutions//
+a=100;//percentage of ionization//
+N=(N1*V1-N2*V2)/V;
+printf('The normality of resultant solution is %fg.equivalent/lit',N);
+H=N*a/100;
+printf('\n the H+ concentration of resultant solution is %fg.ion/lit',H);
+pH=-log10(H);
+printf('\n the pH of resultant solution is %f',pH);
+
diff --git a/615/CH2/EX2.7/2_7.sce b/615/CH2/EX2.7/2_7.sce
new file mode 100755
index 000000000..453609147
--- /dev/null
+++ b/615/CH2/EX2.7/2_7.sce
@@ -0,0 +1,16 @@
+//acids and bases//
+//example 2.7//
+N1=1/10;//normality of NaOH//
+N2=1/20;//normality of HCl//
+V1=1;//volume of NaOH in lit//
+V2=1;//volume of HCl in lit//
+printf("Since NaOH is stronger than HCl,the resultant solution will contain excess of NaOH");
+V=V1+V2;//volume of resultant solution//
+N=(N1*V1-N2*V2)/V;
+printf("\nOH- ion concentration is %fg.ion/lit",N);
+k=1*10^-14;//ionization constant of water//
+H1=k/N;
+H=H1/10^-13;
+printf("\nH+ ion concentration is %f*10^-13g.ion/lit",H);
+pH=-log10(H1);
+printf("\npH of the solution is %f",pH);
diff --git a/615/CH2/EX2.8/2_8.sce b/615/CH2/EX2.8/2_8.sce
new file mode 100755
index 000000000..56cf9234b
--- /dev/null
+++ b/615/CH2/EX2.8/2_8.sce
@@ -0,0 +1,12 @@
+//acids and bases//
+//example 2.8//
+W=2;//weight of NaOH dissolved in water in grams//
+M=40;//molecular weight of NaOH//
+N=W/M;//normality//
+a=100;//percentage of ionization//
+printf('the normality of NaOH solution is %fg.equivalent/lit',N);
+OH=N*a/100;//the OH- ion concentration of solution//
+Kw=10^-14;
+H=Kw/OH;
+pH=-log10(H);
+printf('\n The pH of the NaOH solution is %f',pH);
+\ No newline at end of file
diff --git a/615/CH2/EX2.9/2_9.sce b/615/CH2/EX2.9/2_9.sce
new file mode 100755
index 000000000..c21cdbad7
--- /dev/null
+++ b/615/CH2/EX2.9/2_9.sce
@@ -0,0 +1,11 @@
+//acids and bases//
+//example 2.9//
+M=0.001;//molarity of benzoic acid//
+N=M;//normality of benzoic acid//
+V=1/N;
+K=7.3*10^-5;//dissociation constant of benzoic acid//
+a=sqrt(K*V);//since benzoic acid is very weak//
+printf('the degree of ionization of the solution is %f',a);
+H=N*a;
+printf('\n The H+ concentration of the solution is %fg.ion/lit',H);
+