Science Periodical Test Review

Second Periodical Test Review

• Copper and aluminum are used in cooking pans due to their excellent heat conductivity.
• When oxygen combines with magnesium, it tends to share two electrons.
• Covalent compounds do not conduct electricity when dissolved in water because their bonds are weak.
• Examples of organic compounds include vinegar, liquefied petroleum gas, and nail polish remover.
• Organic compounds contain carbon and can be produced by living things or artificially.
• Butane (C₄H₁₀) is a hydrocarbon with 4 carbon and 10 hydrogen atoms.
• The presence of double bonds is a key characteristic of alkenes, differentiating them from other hydrocarbons.
• Cooking gas is a mixture of propane (C₃H₈) and butane (C₄H₁₀).
• Isomers are organic compounds with the same functional groups but different arrangements.
• Propane (C₃H₈) is a hydrocarbon with a double bond.
• Calcium carbide in water produces acetylene, used for metal melting.
• Carbonyl compounds have functions like cleaning, preserving, and embalming.
• Carbon monoxide is a toxic byproduct of incomplete hydrocarbon combustion.
• Acetone is an organic solvent used in pharmaceuticals.
• Kerosene and liquefied petroleum gas are highly flammable organic compounds.
• Kerosene can be used for cooking.
• Lubricating oil minimizes friction in bicycle ball bearings.
• One mole of a substance contains Avogadro's number (6.02 x 10²³).
• Moles are used to measure the amount of substance.
• Washing soda (sodium carbonate, Na₂CO₃) has a formula mass of 106 g/mol.
• Phosphoric acid (H₃PO₄) has 31.6% phosphorus by mass.
• Molecular mass is used for covalent compounds.
• Acetone ((CH₃)₂CO) has a molecular mass of 58 g/mol.
• A silicon chip (in an integrated circuit) with 6.2 grams has 0.22 moles and 1.3 x 10²⁵ silicon atoms.
• The molar mass of a compound is the sum of its element molar masses.
• The molecular mass of water (H₂O) is 18 g/mol. Six grams of water contain 0.33 moles.