Browsing by Author "Ombaka, Ochieng"

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Adsorption of Lead (II) Ions from Aqueous Solutions Using Mangroves Roots (Rhizophora Mucronata) Charcoal-Carbon Nanotubes Nanocomposite
(Journal of Multidisciplinary Engineering Science and Technology (JMEST), 2021) Ngugi, Fidelis; Mwangi, Joel; Njagi, Eric; Ombaka, Ochieng
Providing clean and affordable water to meet human needs is a grand challenge of the 21st century. Worldwide, water supply struggles to keep up with the fast growing demand, which is exacerbated by population growth, global climate change, and water quality deterioration. Nanotechnology holds great potential in advancing water treatment to improve water treatment efficiency. In this study, Mangrove Roots Charcoal and Carbon Nanotubes (MRCCNTs) nanocomposite was synthesized and utilized as a novel adsorbent for the removal of lead ions from aqueous solutions. The efficacy of MRC-CNT nanocomposites was investigated in batch mode which involved the effects of pH, temperature, concentration of the lead ions, adsorbent mass and contact time on adsorbates removal. Characterization of the adsorbent was carried out by Scanning Electron Microscopy (SEM) to observe the morphology of the adsorbent and surface area analysis and Energy Dispersive X-ray spectroscopy (EDX) to determine the elemental composition of the adsorbent. Adsorption isotherm models and adsorption kinetic studies were used for data analysis. It was observed that the removal efficiency of Pb (II) ions depended on pH of solution and the maximum efficiency was noticed at pH 7 with adsorption capacity of 3.629 mg/g which was calculated by the Freundlich isotherm model. Kinetic studies were well suited and found in good agreement with pseudo-second order. The results indicated that MRC-CNT nanocomposites would be a promising adsorbent for adsorption of Pb (II) ions from aqueous solutions.
Adsorption of rhodamine b from aqueous solution using mangroves (Rhizophora mucronata) carbon nanotubes nanocomposites
(www.allsubjectjournal.com, 2021) Ngugi, Fidelis; Mwangi, Joel; Njagi, Eric; Ombaka, Ochieng
The use of dyes has increased dramatically and uncontrollably in last few decades. Different types of dyes are frequently employed in plastics, paper, cosmetics, leather, and textile industries for coloring purposes. These dyes are released in water as effluents, which are of low Biological Oxygen Demand (BOD) and high Chemical Oxygen Demand (COD). Some of these dyes also are toxic and carcinogenic in nature. This study report on the synthesis of Mangroves Roots-Carbon Nanotubes (MRC-CNT) nanocomposite as an adsorbent for efficient removal of Rhodamine B (Rh. B) dye from aqueous solution. Effect of contact time, initial concentration of dye, pH, and shaking speed on adsorption behavior were systematically investigated. The data obtained were fitted into Langmuir, Freundlich, Dubinin-Rudishkevich (D-R), and Temkin adsorption isotherm models for evaluation of adsorption parameters. The results indicated that MRC-CNT nanocomposite would be a promising adsorbent for adsorption of Rh. B from aqueous solutions.
Analyses of geophagic materials consumed by pregnant women in Embu, Meru and Chuka towns in eastern province, Kenya
(2011) Mwangi, Gichumbi J.; Ochieng, Ombaka; Mwangi, Gichumbi, J.; Ombaka, Ochieng
Geophagy is the deliberate consumption of soil and clay deposits by animals, including man. During pregnancy all the nourishment needed by the developing fetus comes from the mother, either the food she eats or the supplement she may take. The geochemical and mineralogical composition of the materials which are consumed by pregnant women from Meru, Embu and Chuka open air markets were studied. The geophagic materials were subjected to standard digestion procedures and analyzed for full assay and elemental analysis for Co, Zn, Mg, Cu, Pb and Cd using Atomic absorption spectrometry and Energy-dispersive x-ray fluorescence spectrometry in 30 geophagic samples. The mineralogical composition was investigated using X-ray diffractometry (XRD). The geochemical analysis revealed that the geophagic materials contain high levels of silica from 48.59 to 60.27%. Geophagic materials from Embu showed the highest concentration of Pb at 0.96 ppm. The levels of Pb in all samples exceeded the levels recommended by WHO/FAO limits of 0.01 ppm. The levels obtained for Cd in all the samples did not exceed the WHO/FAO limits of 0.003 ppm. The XRD data showed that the geophagic materials of the area consisted mainly of silica.
Assessment of indegenious knowledge and practices on the use of clay among rural communities in Meru, Kenya
(2017) Mwiandi, Felicity Kaari *; Ombaka, Ochieng
A survey was conducted to ascertain the clay applications and its health effects on humans among the rural communities. Household survey, focus group discussion and direct observation were employed. A structured questionnaire with reliability coefficient of 0.82 was used to collect data. Majority of respondents were male (51.2%) aged 21 to 40 years, had primary education (32.2 %), monthly income below Ksh.5,000 (69.0 %) mainly from farming (47.1 %) and brickmaking (31.6 %); and less than 10 years (38.5 %) in clay production. Traditional applications of clay were pottery (81.0 %), brick making (55.7 %), cooking jikos (94.9 %) and plastering walls / floors (70.1 %). Food cooked from clay pots was perceived to taste different from those prepared using conventional utensils (91.3%). Most respondents (79.8%) ascertained that, they experienced skin irritation during clay production processes. The study findings give an insight of existing traditional clay applications. Furthermore it forms the basis on which the probable clay minerals in the study area can be explored for modern applications.
The Banach Numerical Range for Finite Linear Operators
(Modern Scientific Press, Florida, USA, 2019-01) Ohuru, Priscah M.; Musundi, Sammy Wabomba; Ombaka, Ochieng
The numerical range has been studied extensively in Hilbert spaces. Properties of the numerical range such as non-emptiness, containment of the spectrum and in particular, convexity have been proved and results have been given in these spaces. Furthermore, comparison of the numerical ranges with the spectra have been established. In this study, we consider the Banach space numerical range for a linear operator based on the definition by Lumer (1961) and establish its properties in relation to the above stated. Properties of the corresponding Banach numerical radius and spectrum are also discussed.
). Characterization and classification of clay minerals for potential applications in Rugi ward, Kenya.
(African Journals Online, 2016-11-16) Ombaka, Ochieng
The applications of various clayey minerals are related to their structural, physical and chemical characteristics. The physical and chemical properties of the clayey minerals dictate their utilization in the process industries and beneficiation required before usage. The study aimed at establishing the potentiality of clayey minerals from the study area, and the possibility of exploring and exploiting them in order to spur industrial development and promote economic self reliance of Kenya as a nation. The plasticity, particle size, surface area, chemical and mineralogy composition, morphological, thermal analysis and other physical properties were studied using various techniques. The clay samples composed of albite (5-16.7%), kaolinite (11.4-36.2%), microcline (15.2-35.3%), quartz (24.3-68.1%), hornblende (7.6% in samples from Ngamwa only), and other mineral impurities in small amounts. Ngamwa clayey materials consist of high impurities of chemical oxides such as TiO2, MnO, MgO and Fe2O3. Generally, quartz and iron were the major impurities present in the samples from the concerned sites. The findings shows that clayey minerals from the study area can be exploited for commercial production of ceramic products after beneficiation using low cost and environmental friendly techniques in order to reduce the levels of iron, quartz, and other impurities to acceptable levels.
Characterization and classification of clay minerals for potential applications in Rugi Ward, Kenya
(2016) Ombaka, Ochieng
The applications of various clayey minerals are related to their structural, physical and chemical characteristics. The physical and chemical properties of the clayey minerals dictate their utilization in the process industries and beneficiation required before usage. The study aimed at establishing the potentiality of clayey minerals from the study area, and the possibility of exploring and exploiting them in order to spur industrial development and promote economic self reliance of Kenya as a nation. The plasticity, particle size, surface area, chemical and mineralogy composition, morphological, thermal analysis and other physical properties were studied using various techniques. The clay samples composed of albite (5-16.7%), kaolinite (11.4-36.2%), microcline (15.2-35.3%), quartz (24.3-68.1%), hornblende (7.6% in samples from Ngamwa only), and other mineral impurities in small amounts. Ngamwa clayey materials consist of high impurities of chemical oxides such as TiO2, MnO, MgO and Fe2O3. Generally, quartz and iron were the major impurities present in the samples from the concerned sites. The findings shows that clayey minerals from the study area can be exploited for commercial production of ceramic products after beneficiation using low cost and environmental friendly techniques in order to reduce the levels of iron, quartz, and other impurities to acceptable levels.
COMPLEXOMETRIC DETERMINATION OF ZINC USING HYDROXYTRIAZENE AS A METALLOCHROMIC INDICATOR
(2020) Ombaka, Ochieng
New metallochromic indicators belonging to the class of hydroxytriazenes has been evaluated for the direct complexometric determination of Zinc in the presence of diverse ions. Reagent no (i), (ii) and (iii) has been found to be excellent indicators in the titration with EDTA at pH 6.95-7.50, 6.90-7.60 and 7.00-7.50 respectively. The colour at the end point was from light green to colourless and the titration was carried out between temperature range of 20-600C. Cl- , Br- ,CH3COO- , CO3 2- , SO4 2- , NO2 - , SO3 2- , F- , NO3 - , I- , S 2- , WO4 2- , MO7O24 6- , NH4 + , Na+ , K+ , U(VI), Mn(II), Ba(II), Hg(II), Sn(II), Cd(II), Mg(II), Ca (II), Zr(IV) can be tolerated in the titration of zinc (II) when they are present in equivalent amount with that of zinc (II). However, PO4 3- , Co (II), Cu (II) and Ni (II) interferes and when present in the environmental samples, separation techniques such as masking and demasking agents must be employed. The utility of the technique was checked by using 3-Hydroxy-3-m-toly-1-0-Carboxyphenyltriazene for estimation of zinc in zinc-copper alloy and the results had a maximum relative error of +1.53 and standard deviation of ±0.0378 using Sodium thiosulphate to mask copper ions, hence the study clearly indicated that reagent no (i) and (ii) which have high sensitivity, high selectivity and fairly a wide pH range can be used as metallochromic indicators for estimation of zinc in environmental sample where zinc is the major element.
Complexometric determination on Nickel (ii) in its synthetic alloys using selected Hydroxytriazene as metallochromic indicator
(2019) Ombaka, Ochieng
A simple, rapid and reasonable selective Complexometric technique for nickel (II) determination using some selected hydroxytriazene as a metallochromic indicator is reported in the present study. The colour change at the end point was from greenish-yellow/yellow to colourless with sharp end point. The pH ranges were 9.3-9.7, 9.0-9.5, 8.5-9.0, 8.0-8.5 while temperature ranges were 25-60, 25-60, 25-60, 25-50 and 25-50 0C for reagent (i), (ii), (iii), (iv), and (v) respectively. Nickel(II) was determined accurately up to concentration as low as 3.0x10-3M for reagents (ii), (iv), and (v)) while for reagents (i) and (iii) the concentration range could be even lowered to 1.0x10-3M for the determination of nickel (II). The ions such as Cl-, Br-, CH3COO-, CO32-, PO43-, SO42-, C2O42-, S2O32-, NO2-, SO32-, S2-, HPO42-, F-, NO3, WO42-, MO7O246-, I-, NH4+, Na+, K+ did not show any interference in the determination of nickel (II) even when they were present in tenfold excess. Ba2+, Mg2+, Ca2+, were tolerated up to five-fold excess. However Mn2+, Pb2+, Hg2+, Sn2+, Th4+, Cd2+, Co2+, Cu2+,Zn2+, interfered even at equivalent amount. The method was used to determine nickel in its synthetic alloy with maximum relative error of 0.78 when using secondary masking agent.
Concentration of Inorganic Contaminants in Shallow Borehole Water in Chuka Sub-County, Kenya
(Journal of Chemical, Biological and Physical Sciences, 2020-11-24) M. Rugendo, Edith; C. Njagi, Eric; Ombaka, Ochieng
Groundwater from shallow aquifers is an important source of portable water in Chuka Sub-County. However, most shallow boreholes in Chuka Sub-County are undocumented and susceptible to contamination by both geogenic and anthropogenic activities. This study was conducted to evaluate the quality of shallow boreholes water in Chuka Sub-County. Samples were collected from twenty boreholes in Chuka Sub County during the dry and wet seasons. The temperature, pH and conductivity were determined in situ using a meter. The concentration of cations was determined using ICP-MS. The concentrations of anions were determined using standard APHA analytical methods. The temperatures and conductivities of borehole waters were within the limits set by KEBS and WHO. The pH of water in most boreholes during the wet season was within the limits set by KEBS and WHO for portable water. However, borehole water at Karandini (T15) was highly acidic (pH of 3.95) during the wet season. During the dry season, borehole waters were slightly acidic (4.42 - 6.44) except for the borehole at Ndagani market (T11), whose water was alkaline (pH = 8.75). The concentrations of trace and toxic cations and anions (NO3 - , SO4 2- , Cl and PO4 3- ) were within the limits set by KEBS and WHO. However, the concentration of nitrate in several boreholes during the dry season was within the range that cause chronic health effects. Groundwater from most boreholes in Chuka Sub-County is generally safe for domestic uses but require regular monitoring for quality.
Determination of essential minerals and toxic elements composition of the natural licks consumed by livestock in Tharaka-Nithi County, Kenya
(2015-11) Nderi, Onesmus; Musalia, Levi; Ombaka, Ochieng
The aim of this study was to determine the quantities of essential and toxic elements in the natural licks consumed by livestock in Igambang'ombe Division in Tharaka-Nithi County, Kenya. Ten highly used licks, five moderately used licks and one abandoned lick were randomly selected. Mineral elements were determined using TXRF, atomic absorption and U-V visible spectrometry methods. Normal averaging and ratio sacle were used to determine the differences in quantities of mineral elements in the licks and control. Results indicated that, Kimenyi lick had the highest quantities of calcium (44,445±425 mg/kg) and magnesium (26,640±85 mg/kg), whereas Kigwanga, Kibuuri and Kieroo licks showed higher levels of sodium (11,279±35 mg/kg), potassium (1,800±12 mg/kg) and phosphorus (67 mg/kg) than control respectively. Levels of iron ranged between 15,252±166 to 67,717±351 mg/kg. Among the toxic elements only vanadium in Riankui lick site was above the globally accepted median range and the rest were below. The study revealed that natural licks had higher levels of essential elements than control sample, and there was no lick that contained high levels of all the minerals than in other licks. Mineral supplementation could be the major reason why livestock consume natural licks in Igambang'ombe Division.
Determination of Essential Minerals and Toxic Elements Composition of the Natural Licks Consumed By Livestock in Tharaka-Nithi County, Kenya
(2015-11) Nderi, Onesmus Munene; Musalia, Levi; Ombaka, Ochieng
Consumption of natural licks is common among domestic animals under natural circumstances, and as a substitute to commercial mineral licks among smallholder livestock keepers in Tharaka-Nithi County, Kenya, with a believe that animals obtain potential nutritional benefits. However, this has never been established through an experimental research using natural licks from the study area. Therefore, this study was aimed at determining feed intake, nutrient digestibility and milk production performance in dairy goats fed on natural licks. Four lactating Kenya Alpine Dairy Goats (KADG) in their second lactation stage and weighing 47.5 ± 3 kg were randomly assigned four treatment diets that consisted of three natural licks from Kang'au, Nagundu and Kabariange, and a standard commercial lick (control) in a 4 by 4 Latin square design. A basal diet of Boma Rhodes grass hay and a standard concentrate were fed to the animals, and feed intake, fecal output and milk yield were measured. One way Analysis of Variance (ANOVA) model was used for the lick intake, nutrient intake, and apparent digestibility and milk parameters. Correlation analysis was carried out to establish the relationship between natural lick sources and milk parameters. There was no significant difference on dry matter intake, nutrient intake, apparent digestibility and milk yield and quality (P > 0.05) among goats consuming natural licks compared to commercial lick. However, there was a positive correlation (r) with a value of 0.70 between milk production and lick intake. Natural licks can be an alternative source of mineral supplementation where commercial mineral licks are not available.
Effect of Human Activities and Seasonal Variation on Water Quality of Nkenye (Chikuu) Stream in Chuka, Kenya
(2013-01) Ombaka, Ochieng; Gichumbi, Joel M.; Mukono, Simon T.; Kibara, D.
Composite water and sediment samples were taken from Nkenye stream at five different sampling stations during wet and dry seasons. Water quality parameters were analyzed using standard methods to ascertain the effect of human activities on the water quality. The variations in the physicochemical and biological parameters were observed from station to station both in the dry and wet seasons. These variations were attributed to human activities. Results showed significant seasonal variation in most measured parameters with a few showing significant spatial variation. The characteristics of the water from the stream revealed an acceptable quality for most of measured parameters when compared with drinking water standards. However, high values of turbidity, iron, manganese, chromium and microbial load were recorded compared with drinking water standards, which call for proper treatment of the water before being used by the public. The results of sediment samples revealed that silicate, iron, aluminum are present in major quantities while other minerals are present in trace amounts. Thus the present study concludes that Nkenye stream water is contaminated and needs attention for it to be safe for domestic use. (2) (PDF) Effect of Human Activities and Seasonal Variation on Water Quality of Nkenye (Chikuu) Stream in Chuka, Kenya. Available from: https://www.researchgate.net/publication/305771233_Effect_of_Human_Activities_and_Seasonal_Variation_on_Water_Quality_of_Nkenye_Chikuu_Stream_in_Chuka_Kenya [accessed Nov 03 2020].
Indigenous knowledge and applications of clay among rural communities in western Kenya
(2019-01) Kaari, M. F.; Ombaka, Ochieng
A survey was conducted in Western Kenya involving 281 respondents to ascertain the clay applications and its health effects on human beings. Household survey, focus group discussions and direct observation were employed. A structured questionnaire with reliability coefficient of 0.88 was used to collect data and analyzed using SPSS. Majority of respondents were females (50.2%) aged 21 to 40 years, had secondary education (60.5%), monthly income was below Ksh.5,000 (63.3%), earned income mainly from brickmaking (59.4%), farming (21.0 %) and experience of 6-10 years in making clay products to earn a living (41.6%). Residents acquired information on clay from relatives/friends (31.7 %) and other farmers (34.2 %). They utilized clay mainly for brickmaking (54.8 %), plastering floors and walls (48.1%) and pottery (24.5%). Food cooked from clay pots tastes different compared to conventional utensils (70.0%). 43.3 % of respondents complained of skin irritation after prolonged exposure to clay material during clay handling. The study findings are significant as they unearth the indigenous knowledge of clay in the study area which will facilitate the researchers on understanding the basics of these clays as they explore advanced technological applications.
NEW METALLOCHROMIC INDICATORS FOR COMPLEXOMETRIC TITRATION OF COPPER (II) IN PRESENCE OF INTERFERING SPECIES
(Life Science Informatics Publications, 2020-09) Ombaka, Ochieng
Six hydroxytriazenes has been introduced as a metallochromic indicator in the complexometric titration with EDTA and applied successfully to the titration of copper (II). A direct method of titration of Cu (II) with EDTA using these hydroxytriazenes has been proposed. The change of colour of the solution at the end point during titration was from yellow to green at a pH range of 5.5-6.0, 5.05-5.50, 5.0-5.5 for reagent number (i, ii, iii, vi), iv, v respectively. The titration can be performed at the temperature range of 25-60℃. The minimum concentration of copper (II) which can be titrated is as follows: 1.0 x 10−3 M Cu (II), 3.0 x 10−3M Cu (II), 5.0 x 10−3M Cu (II) when using reagent number (i, iii, v, vi), iv, ii respectively as metallochromic indicators. Interference studies of a number of cations and anions have been studied. Cl−, Br−, CH3COO−, PO4 3−, SO4 2−,C2O4 2−, S2O3 2−, NO3 −, SO3 −, S 2−, HPO4 2−, F −, NO3 −, WO4 2−,Mo2O24 6− , I −, NH4 +, Na+, K +, Ba2+, Hg2+, Mg2+, Ca2+ can be tolerated on the titration of Cu (II) up to tenfold excess. However, {U(vi), Sn(II), Zr(iv), Co(II), Zn(II), Ni(II)}, {Pb(II), Th(IV)}, {Mn(II), Cd(II)} interfered at equivalent amounts, fivefold excess, tenfold excess respectively.
Physicochemical Proprieties of Pond Water in the Economic Stimulus Programme (ESP) Fish Ponds in Tharaka-Nithi County, Kenya
(International Journal of Interdisciplinary Research and Innovations, 2020) Kibaara, David Ithigi; Magana, Adiel Micheni; Githae, Eunice Wmamu; Ombaka, Ochieng
In an effort to attain food security, Kenya has embraced aquaculture as one of its strategies. From 2009, the Government established thousands of fish ponds through the Economic Stimulus Programme (ESP). TharakaNithi County was one of the places covered by the ESP and has 95% of its total ponds under the programme, stocked with the Nile tilapia (Oreochromis niloticus). Physicochemical properties of water influence overall pond productivity and fish yields. The ponds in Tharaka-Nithi County have suffered low production, the average production remaining at <30% of potential, with reports of stunting and frequent fish mortalities. This study aimed to investigate the physicochemical properties of the pond water in the county. Using the randomized complete block design (RCBD), the study area was divided into three zones whereby 27 fish ponds were studied. Chemical analysis was done according to the APHA Standard Methods and data analyzed using the one-way ANOVA. The Statistical Package for the Social Sciences (SPSS) Version 22.0 was used for correlations and regression analyses. Significant differences (p ˂ 0.05) were found in water temperature, dissolved oxygen, transparency, pH and conductivity among ponds in the three zones. Water temperatures, ammonia and PO4-P concentrations were outside the recommended range for optimum O. niloticus growth. Occasionally, DO and pH were outside those suitable for optimum tilapia growth, which could explain the frequent fish deaths and low aquaculture production. Regular monitoring of physicochemical parameters is recommended. These findings will be used by relevant government agencies and fish farmers to enhance fish production.
Sensitivity analysis of treatment and counselling in a co-infection model of HIV/AIDS, tuberculosis and malaria
(2016-02) Ombaka, Ochieng
This study presents a co infection deterministic model defined by a system of ordinary differential equations for HIV/AIDS, malaria and tuberculosis. The model is analyzed to investigate the potential impact of counseling and treatment on disease progression by carrying out sensitivity analysis of the reproduction number with respect to counseling and treatment. The sensitivity indices of the reproduction numbers RH, RHM, RHT and RHMT with respect to treatment and counseling for the HIV/AIDS individuals showed that counseling is the most sensitive parameter in controlling the co infections.
Spectrophotometric Determination of cobalt (II) in low concentrations using hydroxytriazene as selective chelating agents
(2011-12) Ombaka, Ochieng; Gichumbi, J. M.
The present work describes a selective, rapid and simple spectrophotometric method for the determination of cobalt (II) at trace levels using some selected hydroxytriazene. The method is based on the reaction of hydroxytriazene at pH 5.5 to 6.2, 6.0 to 6.8, 7.1 to 7.35, 7.3 to 7.9, 6.75 to 7.25 and 7.2 to 7.75 for hydroxytriazenes no (i), (ii), (iii), (iv), (v) and (vi) respectively and ethanol media with cobalt (II) to produce a highly absorbent yellow coloured chelate product with an absorption maximum at 393,397,417,406,410 and 412 nm for hydroxytriazenes no. (i), (ii), (iii), (iv), (v) and (vi), respectively. The reaction is instantaneous and the absorption remains stable for 24 Hrs. The average molar absorption coefficient were 1.1 x 104, 1.2 x 104,1.8 x 104, 2.5 x 104, 2.1 x 104, 1.9 x 104 mol-1 dm3 cm-1 for hydroxytriazene no (i), (ii), (iii), (iv), (v), (vi) respectively and Sandell’s sensitivity in ng/cm2 were 5.4, 4.9, 3.3, 2.4, 2.9 and 3.1 for hydroxytriazene no. (i), (ii), (iii), (iv), (v) and (vi), respectively. The stoichiometric composition of the chelate is 1:3 for hydroxytriazene no (i), (iv), (v), (vi), 1:2 for (ii) and 1:1 for (iii). A large excess of over 30 cations, anions and complexing agent do not interfere in the determination at equivalent amounts. The method was successfully used in Mussaenda arcu. The method has high precision and accuracy.
Spectrophotometric Determination Of Copper (Ii) In Soil From Ahero Rice Irrigation Schemes Using Hydroxytriazene
(IOSR Journal of Applied Chemistry, 2020) Ombaka, Ochieng
A simple, rapid, sensitive and cost effective spectrophotometric technique for the determination of copper (II) using 3-hydroxy-3-m-tolyl-1-O-carboxyphenyltriazene has been reported. The complex formed was greenishyellow having stoichiometry of 1:1 (Cu (II): hydroxytriazene) at a pH range of 6.0-6.6. The measurements were carried out at a working wavelength of 405nm with a molar absorptivity of 2.8×104Lmol-1 cm-1and sandell’s sensitivity of 2.26ng/cm2 . Lambert –Beer’s law is obeyed over a range of 1.27-7.63mg/L of copper. The correlation coefficient of the standard calibration curve was 0.997. The complex formed between copper (II) and hydroxytriazene was greenish –yellow with composition of 1:1(Cu (II): hydroxytriazene). The relative standard deviation (n=10) for standard dilution of 635.46mgL-1 copper (II) was 0.92%. The change in Gibb’s free energy at 270Cwas determined using Purohit’s, Harvey and Manning’s method and found to be respectively. The study showed that, the following cations and anions do not interfere when present at equivalent amount of copper: Cl- ,Br- , CH3COO- , CO3 2- , PO4 3- ,SO4 2- , C2O4 2- , I- , S2O3 2- , NO2- , SO3 2- ,S2- ,HPO4 2- , F- , NO3 - , WO4 2- , MO7O24 6- , NH4 + , Na+ , k + , Ba2+ , Cd2+ , Mg2+ , Ca2+ . However, UO2+ , Mn2+ , Pb2+ , Hg2+ , Sn2+ , Th4+,ZrO2+,Co2+ , Zn2+, Ni2+ interferes with copper (II) determination at equivalent amount, hence the need for the masking agent. The present method was applied to the determination of copper (II) in agricultural soil samples.