Anion Y − có cấu hình electron: 1s22s22p63s23p6. Trong bảng tuần hoàn Y thuộc ( giải thích) A. chu kì 3, nhóm VIIA. B. chu kì 3, nhóm VIA.

C. chu kì 3, nhóm VIIIA. D. chu kì 4, nhóm IA.

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

In an exothermic reaction the bonding energy of the product is: less than the reactants same as the reactants greater than the reactants dependent upon the presence of a catalyst

The boiling point of propanoic acid is higher than that of 1-butanol because: propanoic acid has a higher molecular weight than 1-butanol. propanoic acid is more soluble in water than 1-butanol. propanoic acid is a better hydrogen bond donor than 1-butanol. propanoic acid forms hydrogen bonded dimers and 1-butanol does not. 1-butanol forms hydrogen bonded dimers and propanoic acid does not.