Effects of Roofing Sheets On Harvested Water Run-Off in Ichida, Anambra State.


Harvested run-off from five houses with stone-coated was sampled in Ichida, state for the of the roof on the harvested water.

The pH and metal content of the harvested water run-off were analyzed. The result of the analysis was compared with the World Health Organization standard.

The results showed that the pH ranged from 6.4 ­– 7.2 and the concentration of the heavy metals for lead range from 0.143 –­­ 0.244, for copper 0.011– 0.066, for aluminum range from 0.00 – 0.085, for silicon range from 0.0191 – 0.748, for iron rage from 0.033 – 0.122, for zinc range from 0.323 – 0.665 and for chromium range from 0.108 – 0.213.

It was observed that all the lead, the silicon content of all the 5 houses, and the aluminum content of houses 2 and 5 were above the WHO standard, whereas others were all below the WHO standard. Harvested water run-off is hazardous to health.


Background of Study

Priestly in 1781 was the first to observe that the explosion of a hydrogen-and-oxygen gas mixture yields water vapor.

Later, Cavendish established that the ratio by volume of hydrogen to oxygen in that reaction at constant temperature and pressure was 2:1.

Water is one of the most important and abundant compounds of the ecosystem. All living organisms on the earth need water for their survival and growth.

It rarely occurs in its pure form in nature (Ababio, 2005). It is the only substance that exists naturally on Earth in all three physical states of matter; gas, liquid, and solid.

Water has a number of unique chemical and physical properties that make it essential for life. Almost all liquids contract when they get colder and reach a maximum density when they solidify.

As the water cools, it contracts until it reaches 4°C, then it expands until it freezes at 0°C. Ice is less dense than water which allows ice cubes to float in a soft drink, icebergs to float in the ocean, and ponds and lakes to freeze from the top down so that aquatic plants and animals can survive in the unfrozen liquid below.

Water molecules have a simple structure: two hydrogen atoms bonded to one oxygen atom H2O. This simple structure is responsible for water’s unique properties.

The bond between each hydrogen atom and the oxygen atom results from a pair of electrons shared between the two atoms.

In water, the electrons in the shared pair are not shared equally between the hydrogen and oxygen atoms. The oxygen atom has a greater affinity for electrons than the hydrogen atom, and the electrons in the O–H bond are more attracted to oxygen.

Because electrons have a negative charge, the unequal sharing in the O–H bond results in oxygen acquiring a partial negative charge (−) and hydrogen a partial positive charge (+). The H–O–H bond angle in water is 104.5°, which means that the molecule has a bent shape.


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