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Types of chemical formula:
Empirical Formula: This gives the simplest whole-number ratio of atoms in a compound. For example, the empirical formula of hydrogen peroxide (H₂O₂) is HO.
Molecular Formula: This provides the exact number of each type of atom in a molecule. For example, the molecular formula of glucose is C₆H₁₂O₆.
Structural Formula: This shows how atoms are arranged and bonded together in a molecule. There are different types of structural formulas, including:
Lewis Structures: Depict the bonding between atoms of a molecule and the lone pairs of electrons.
Condensed Structural Formulas: Show the arrangement of atoms in a molecule in a more compact form than full structural formulas.
Skeletal Formulas: A simplified representation showing the bonding between carbons in organic compounds.
Ionic Formulas: These show the ratio of ions in a compound. For instance, the formula for sodium chloride is NaCl, indicating a 1:1 ratio of sodium ions to chloride ions.
Components of the chemical formula:
Element Symbols: Each element is represented by a one- or two-letter symbol. For example, H for hydrogen, O for oxygen, and Na for sodium.
Subscripts: Numbers are written at the lower right of element symbols to indicate the number of atoms of that element in the molecule. For example, in H₂O, the subscript 2 indicates there are two hydrogen atoms.
Coefficients: Numbers placed before the formula to indicate the number of molecules. For instance, 2H₂O means there are two molecules of water.
Parentheses: Used to indicate a group of atoms that behave as a single unit in a compound. For example, in calcium phosphate, Ca₃(PO₄)₂, the parentheses group the phosphate ions.
Charges: For ions, the charge is shown as a superscript at the end of the formula. For example, Na⁺, Cl⁻, SO₄²⁻.
Examples:
Water (H₂O): Two hydrogen atoms and one oxygen atom.
Carbon Dioxide (CO₂): One carbon atom and two oxygen atoms.
Sulfuric Acid (H₂SO₄): Two hydrogen atoms, one sulfur atom, and four oxygen atoms.
Methane (CH₄): One carbon atom and four hydrogen atoms.
What is a complete molecular equation with respect to ions and molecules?
A solution of a substance X is used for white washing.name the substance X and write its formula.
Why does the colour of copper sulphate solution change when an iron nail is dipped in it?
Identify the substance that are oxidised and the substances that are reduced in the following 4Na(s) + O2(g) = 2NaO(s)
What happens when dilute hydrochloric acid is added to iron fillings?
Why do we store silver chloride in dark coloured bottles?
why do silver articles turn black when kept in the open for few days.name the phenomenon involved.
Give the characteristics test for CO2 ,SO2,O2,H2