Chemistry Section 2

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• The unit of the rate constant (k) for a zero order reaction is the same as that of the rate of reaction.
• Acid rain may contain both H2SO4 and HNO3.
• Sodium is an element that conducts electricity and melts below 100°C.
• Ethylene bromide is added to leaded gasoline to prevent engine deposits.
• Isotopes differ in their chemical properties.
• The volume occupied by 1.4g CO at STP is 1.12 dm3.
• The set F – Ne – Na+ has all species that are isoelectronic.
• Mg (CIO4)2 is the water absorber used in combustion analysis.
• The choice of filtering media for filtration depends on the nature of the precipitate.
• Solvent extraction is a method of separation using the distribution law.
• In a mixture of equal masses of methane and oxygen at 250°C, the fraction of total pressure exerted by oxygen is one-third.
• CO2 in dry ice forms a molecular crystal.
• Only London dispersion forces are present among the molecules of solid iodine.
• The quantum number values for 3p orbitals are n=3, l=1.
• N2-2 is the species with unpaired electrons in antibonding molecular orbitals.
• For a given process, the heat change at constant pressure (qp) is greater than the heat change at constant volume (qv).
• The maximum concentration of Ag+1 ions in a solution of AgCl with a solubility product of 2.0 x 10^-10 mol2 dm-6 is 1.414 x 10^-5 mol dm-3.
• A 5.85% NaCl solution has the highest boiling point.
• Nickel cadmium cells can be used in laptops.
• The unit of rate constant (K) for a zero order reaction is mol dm-3 s-1.
• Ethane is produced when ethyl chloride is reduced in the presence of Zn/HCl.
• Cu2Cl2 is the catalytic promoter used in the industrial preparation of CH3CHO.
• Phthalic acid is not a fatty acid.
• Urea provides both nitrogen and phosphorus to plants.
• Carbon dioxide in water can make chlorination harmful.
• The mass of one mole of an electron is 0.55 grams.
• The number of atoms in a molecule determines its atomicity.
• Calcium has the same isotopes as palladium.
• A limiting reactant gives the minimum amount of the product under consideration.
• A vacuum desiccator is a safe method for drying crystals.
• London dispersion forces are predominant when both a and b values are small.
• Plasma is used in fluorescent bulbs, neon signs, and lasers.
• Glass is an example of a pseudo-solid.
• Bohr’s model of the atom is contradicted by Heisenberg’s uncertainty principle.
• Atomic radius can be determined using X-ray diffraction.
• The type of reaction where larger molecules break down into smaller ones is pyrolysis.
• The relative lowering of vapor pressure in a solution of 18g glucose in 90g water is one-fifty-first.
• Stronger oxidizing agents have higher standard reduction potentials.
• The anode in a galvanic cell is negatively charged.
• Different isomers can have the same molecular formula but differ in structural formula, called isomers.
• Geometric isomerism is usually found in alkenes.
• Silicones are not used in medicines.
• HgS is the chemical composition of cinnabar.
• The reaction of chlorine with hot caustic soda in sunlight is a disproportionation reaction.
• The coordination number in [Cr(OH)3(H2O)3] is 6.
• The property of carbon chain formation is called catenation.
• Vinyl acetylene reacts with hydrochloric acid to produce chloroprene.
• Toluene reacts with chlorine in sunlight to form benzyl chloride.
• OH- is not a good leaving group in organic compounds.
• The fractional distillation of petroleum produces gasoline up to 20%.
• 2-propanol and 1-propanol show position isomerism.
• Malonic acid is the common name for propane-1,3-dioic acid.
• Epoxy paints are used to coat materials in thermal power stations.
• The main source of organic compounds is plants.
• Aromatic compounds burn with a smoky flame due to their structure.
• The octane number of 2,2,4-trimethylpentane (iso-octane) is 100.
• Geometric isomerism is not exhibited by propene.
• Pentane and 2-methyl butane have the same percentage composition.
• The first organic compound synthesized in the laboratory was urea.
• A double bond consists of one sigma bond and one pi bond.
• The state function that depends on the initial and final state of a system is enthalpy.
• Compounds with the same molecular formula but different structural formulas are called isomers.
• Organic compounds are soluble in non-polar solvents.
• Methane is used in power generation and chemical industries as a natural gas with good caloric value and cost-effectiveness.
• Pyrolysis is the process in which larger molecules break down into smaller molecules at low temperatures and pressures.
• The metallic sound produced by an engine due to pre-ignition of fuel is known as knocking.
• Nickel tetraethyl [(C2H5)4 Pb] can be used as an anti-knocking agent.
• Alkenes can exhibit cis-trans isomerism.
• Compounds containing benzene rings in their structure are called aromatic compounds.
• An amide can be represented by the functional group RCONH2.
• Only sigma bonds are present in ethoxy ethane.
• Ethyne has a linear molecular structure.
• The general formula for cycloalkenes is CnH2n-2.
• C5H12 has three isomers.
• The octane number can be improved by isomerization, adding (C2H5)4 Pb, and adding (CH3)4 Pb.
• The octane number of 2,2,4-trimethylpentane is defined as 100.
• Ethanol and methanol are isomers.
• Benzene is more stable than its Kekulé structure due to resonance.
• Acetone is a polar compound.
• Functional isomerism is not shown by propanal and propanone.
• CFCs are not responsible for ozone layer depletion.
• Isobars are atoms with the same atomic mass but different atomic numbers.
• Electronegativity decreases as you move down a group in the periodic table.
• A positive ion is known as a cation.
• In an exothermic reaction, the energy of the products is lower than the energy of the reactants.
• Sodium loses electrons more readily than magnesium.
• Molar mass is the mass of one mole of a substance in grams.
• Transition elements exhibit variable oxidation states.
• Carbon-12 isotope is used as the standard for atomic mass.
• A solution with a pH of 3 is acidic.
• Calcium has a higher ionization energy than sodium.
• Hydrogen and helium are the most abundant elements in the universe.
• Isotopes have the same number of protons but different numbers of neutrons.
• Ionic compounds conduct electricity in molten state.
• Phosphorus has a higher ionization energy than sulfur.
• A catalyst increases the rate of a chemical reaction by lowering the activation energy.
• The chemical symbol for gold is Au.
• Nitrogen makes up the majority of Earth’s atmosphere.
• The first ionization energy generally decreases as you move down a group in the periodic table.
• A covalent bond involves the sharing of electrons between atoms.
• In a reaction, the oxidizing agent undergoes reduction.
• The mass number represents the sum of protons and neutrons in an atom’s nucleus.
• Fluorine is the most electronegative element on the periodic table.
• Potassium has a lower ionization energy than lithium.
• A base donates OH- ions in aqueous solutions.