A h/mc
B 2h/mc
C h/(2mc)
D Zero
Explanation: Δλ = (h/mc)(1-cos90°) = (h/mc)(1-0) = h/mc = 2.43 × 10⁻¹² m (Compton wavelength).
A Is fixed
B Is continuous up to a maximum value
C Depends on temperature
D Is always zero
Explanation: Beta particles have a continuous energy spectrum from 0 to a maximum value, because energy is shared with the antineutrino.
Explanation: v = cα where α = e²/(4πε₀ℏc) ≈ 1/137 is the fine structure constant. So v ≈ c/137.
A -3.4 eV
B -6.8 eV
C -1.51 eV
D -27.2 eV
Explanation: E₂ = E₁/2² = -13.6/4 = -3.4 eV. First excited state is n=2.
A Less than primary
B More than primary
C Same as primary
D Zero
Explanation: In a step-down transformer, voltage decreases but current increases (conservation of power: VpIp = VsIs).
Explanation: Carbon in CH4 forms four sigma bonds with no lone pairs, giving sp3 hybridization and tetrahedral geometry.
Explanation: Carbon-14 has atomic number 6 (protons = 6) and mass number 14. Neutrons = 14 - 6 = 8.
A Principal quantum number (n)
B Azimuthal quantum number (l)
C Magnetic quantum number (ml)
D Spin quantum number (ms)
Explanation: The azimuthal quantum number (l) determines the shape of an orbital: l=0 is s (spherical), l=1 is p (dumbbell), etc.
A Sodium (Na)
B Magnesium (Mg)
C Oxygen (O)
D Chlorine (Cl)
Explanation: Oxygen has an electronegativity of 3.44 on the Pauling scale, which is higher than Na (0.93), Mg (1.31), and Cl (3.16).
A C6H12O6
B C6H10O5
C C12H22O11
D CH2O
Explanation: Glucose is a monosaccharide with the molecular formula C6H12O6, containing six carbon atoms, twelve hydrogen atoms, and six oxygen atoms.
A Covalent bonding
B Ionic bonding
C Metallic bonding
D Hydrogen bonding
Explanation: NaCl is formed by the transfer of an electron from Na to Cl, creating Na+ and Cl- ions held together by electrostatic (ionic) forces.
Explanation: In K2Cr2O7: 2(+1) + 2(Cr) + 7(-2) = 0, so 2Cr = 12, Cr = +6.
A Boyle\'s law
B Charles\'s law
C Avogadro\'s law
D Dalton\'s law
Explanation: Charles\'s law states V ∠T (at constant P and n), meaning volume increases linearly with absolute temperature.
Explanation: HCl is a strong acid that fully dissociates. [H+] = 0.001 M = 10^-3, so pH = -log(10^-3) = 3.
A Bromine (Br)
B Chlorine (Cl)
C Iodine (I)
D Fluorine (F)
Explanation: The configuration [Ar] 3d10 4s2 4p5 has 35 electrons, which corresponds to Bromine (Z = 35).
A Methanol
B Ethanol
C Propanol
D Ethanal
Explanation: CH3-CH2-OH has a two-carbon chain with a hydroxyl group, so its IUPAC name is ethanol (ethan-1-ol).
A NH3
B OH-
C BF3
D CH3O-
Explanation: BF3 is electron-deficient (boron has only 6 electrons) and can accept an electron pair, making it an electrophile.
A 4 sigma, 1 pi
B 5 sigma, 1 pi
C 4 sigma, 2 pi
D 5 sigma, 0 pi
Explanation: Ethene has 4 C-H sigma bonds + 1 C-C sigma bond = 5 sigma bonds, and 1 C=C pi bond.
A 0.1 M NaCl
B 0.1 M glucose
C 0.1 M CaCl2
D 0.1 M urea
Explanation: Boiling point elevation depends on the number of solute particles. CaCl2 dissociates into 3 ions (i=3), producing the greatest elevation.
A +1.00 V
B 0.00 V
C -1.00 V
D +0.76 V
Explanation: The Standard Hydrogen Electrode (SHE) is assigned a potential of exactly 0.00 V by convention and serves as the reference for all other electrodes.