chemistry sets

When mixed with water, cement sets to a hard mass. It first forms a plastic mass which hardens after some time due to 3-dimensional cross-links between the --Si-O-Si-- and --Si-O-Al-- chains. The first setting occurs within 24 hours whereas the subsequent hardening requires a fo..

. Note: The fast-setting tricalcium aluminate is removed to slow down the setting process. A quick setting will give rise to crystalline hydrated calcium aluminate. A slower setting yields the colloidal gel that imparts greater strength to the set m..

The slaked lime present in the mortar combines with the carbon dioxide of the air to form a hard layered mass of calcium carbonate. When the walls are whitewashed with "milk of lime", a thick suspension of slaked lime in water, carbon dioxide of the air combines with the calcium hydroxide and form..

IUPAC Nomenclature for Elements with Z > 100 - All elements beyond uranium (Z=92) are synthesized in the laboratories and are known as 'trans uranium elements'. The elements, beyond fermium (Z=100) are known as 'trans fermium elements'. These elements have atomic numbers 101 onwards. Elements like ..

To prevent the losses of heat and to protect the persons operating the reactor from the radiation and heat, the entire reactor core is enclosed in a heavy steel or concrete some called the shield. In nuclear power plants, the large amount of energy which is released in the form of heat during cont..

Limestone and clay are the chief raw materials used in the manufacture of Portland cement. Limestone provides calcium oxide. Clay gives silica, alumina and ferric oxide. Note: If lime is in excess, the cement cracks during setting and if it is less, the cement is weak in str..

CO 2 dissolves in water to give carbonic acid. Therefore, carbon dioxide is called carbonic anhydride. Carbonic acid being a dibasic acid forms two sets of salts, the hydrogen carbonates HCO 3 - and carbonates, CO 3 2 ..

Let us examine closely the following sets of compounds and study their properties in terms of their physical state, melting points and boiling poin..

Reinforced concrete is nothing but concrete allowed to set on structures having iron rod framework. This gives extra strength to the structur..

This principle was proposed by Pauli in 1952. It states that no two electrons in an atom can have same values for all the four quantum numbers. Thus, in the same atom, two electrons may have the same values for three quantum numbers but the fourth must be different. Electrons having the same value ..