science experiments for high school

In 1885, Sir William Crookes carried out a series of investigations into the behaviour of metals heated in a vacuum. The experiment of Crookes and others showed that a heated cathode produced a stream of radiation, which could cause gases at low pressure to glow and which made other subs..

From chlorine to iodine, which ionize by accepting one electron there is a decrease in the electron affinity or the energy released. The lower electron affinity of fluorine when compared to chlorine is not fully understood. Element Electron Affinity Fluorine 3.62 eV Chlorine ..

Take some crystals of iodine in an evaporating dish. Cover it with a glass funnel, as shown in figure 2.3. Close the tip of the tail of the funnel with some cotton. Heat the dish gently. The space inside the funnel gets filled with purple vapours of iodine. Stop the heating. The purple vapours soli..

Take a beaker of water. Add a pinch of salt (sodium chloride) and stir. The water dissolves the salt and the salt spreads out throughout the water. Two samples of this solution taken from two different parts of the beaker will have the same composition. So, the solution is said to be homogeneous. G..

Copper taken = 1.179g Copper oxide formed = 1.476g Oxygen present = 1.476 - 1.179 = 0.297g Percentage of oxygen is approximately the same in both the above cases. So the law of constant composition is illustrate..

Take a clean and dry beaker and find it's mass (m) using a physical balance. Now find the weight of a stone by suspending it from a spring balance. Fill an Eureka can (Eureka can is a beaker having a spout near the top) with water filled till the spout. Place the beaker of mass 'm' under the spout...

Aristotle, the great ancient philosopher performed some experiments to study the speed of freely falling objects. He observed that when two bodies of different masses were dropped simultaneously from the same height, the heavier object reached the Earth's surface earlier than the lighter ..

Place a prism (P 1 ) on a table and a screen behind it. Allow a narrow beam of light to be incident on the prism (P 1 ). The white light gets dispersed and we obtain a band of seven colours on the screen. Now remove the screen and place another prism P 2 of the same material in the opposite d..

Sir Isaac Newton, while studying the images of heavenly bodies formed by a lens, found that the images were coloured at the edge..

Couple two spring balances A and B as shown in the figure. When we pull the balance B both the balances show the same reading indicating that both the action and reaction forces are equal and opposit..