Show, mass number, number of protons & electrons, and groups (metal, for example alkali metal, and group I,II etc), name, (for egg fslvium bromide), writhing its formula and colour in solution (show all of them), ion migrations , formula and electron diagram, ionic bond and covalent bond, choice of alloys and their reasons, fractional distillation, fractions and their uses.
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Atoms are the building blocks of matter. Every atom has a nucleus containing protons and neutrons, with electrons orbiting around it. The mass number equals protons plus neutrons, while the atomic number equals the number of protons. In neutral atoms, electrons equal protons. For example, oxygen has 8 protons, 8 neutrons, and 8 electrons.
The periodic table organizes elements into groups with similar properties. Group 1 contains alkali metals like sodium and potassium, which are highly reactive with one valence electron. Group 2 has alkaline earth metals like magnesium. Groups 3 to 12 are transition metals with variable oxidation states. Group 17 contains halogens like chlorine, while Group 18 has unreactive noble gases.
Chemical bonds form when atoms combine. Ionic bonds occur when electrons transfer from metals to nonmetals, creating charged ions like sodium positive and chloride negative in salt. Covalent bonds form when nonmetals share electrons, like in water where oxygen shares electrons with hydrogen atoms. During electrolysis, ions migrate through solutions - positive ions move to the negative electrode while negative ions move to the positive electrode.
Alloys are mixtures of metals designed to improve properties. Steel combines iron with carbon to create a material much stronger than pure iron. Adding chromium makes stainless steel that resists corrosion. Brass mixes copper and zinc for durability and corrosion resistance, perfect for musical instruments. Bronze combines copper and tin for strength. Aluminum alloys provide lightweight strength for aircraft and automotive applications.
Fractional distillation separates crude oil into useful products based on different boiling points. The process heats crude oil in a tall column where lighter fractions with lower boiling points rise to the top, while heavier fractions remain at the bottom. Refinery gas becomes LPG, gasoline fuels cars, kerosene powers jets, diesel runs trucks, lubricating oils service machinery, and bitumen paves roads.