Choose the statements that are true about bonds. a. if atoms have a big electronegativity difference, they form an ionic bond. b. in ionic bonds, electrons are shared between atoms. c. in covalent bonding, electrons are shared between atoms. d. if atoms have a big electronegativity difference, they form a covalent bond.

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.