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Simple bonding theory expects every atom in a covalent molecule to end up with eight valence electrons. Two stable gas-phase molecules, BF3(g) and BeF2(g), do not fit this picture. Which adaptation of the bonding model was needed to explain…
What is the oxidation state of chlorine in Cl2O7? A. −7 B. +3.5 C. +7 D. +14
Which pair of elements reacts together most vigorously? A. Sodium and bromine B. Potassium and bromine C. Sodium and chlorine D. Potassium and chlorine
Phosphorus occurs as the atom and as several ions. In which row are the species arranged from the smallest radius to the largest? A. P3−, P, P3+, P5+ B. P5+, P3+, P, P3− C. P,…
Butanone, CH3COCH2CH3, has the structure shown. One of the following four compounds shares its molecular formula, C4H8O, with butanone. Which compound is this structural isomer of butanone? A. CH3COCH2CH2CH3 B. CH3CH2CH2CHO C.…
In which species does an atom have the oxidation state +5? I. IF5 II. H3PO4 III. N2O4 A. I and II only B. I and III only C. II and III only D. I, II and III
Which statement explains why the atomic radius decreases across period 3 from magnesium, Mg, to sulfur, S? A. The number of occupied main energy levels increases B. The shielding effect of the inner electrons decreases C. The number of protons in the nucleus…
The energy profile below was recorded for a reaction. Which pair of statements is consistent with it? In each option the first statement compares the enthalpy of the products with that of the reactants and the second gives the sign of ΔH. A. products…
Which two functional groups occur in both molecule P and molecule Q? A. Amino and a benzene ring B. Hydroxyl and ester C. Hydroxyl and a benzene ring D. Amino and hydroxyl
Which pair of elements would react together most vigorously? A. Na(s) and I2(s) B. Cs(s) and I2(s) C. Na(s) and F2(g) D. Cs(s) and F2(g)