What are the covalent compounds? why are they different from ionic compounds? List their three characteristic properties.
When ethanol reacts with ethanoic acid in the presence of conc. H2SO4, a substance with fruity smell is produced. Answer the following:
i) State the class of compounds to which the fruity smelling compounds belong. Write the chemical equation for the reaction and write the chemical name of the product formed.
ii) State the role of conc. H2SO4 in the reaction.
i) When ethanol and ethanoic acid react with each other in the presence of concentrated H2SO4 acid, an ester is formed with a fruity smell. The chemical equation for the reaction is given as:
ii) A carboxylic acid is a very weak proton, therefore, the H2SO4 is used to protonate it to be able to react with the acid. However, the reaction is reversible therefore H2SO4 is also used as drying agent to remove water and shift the equilibrium to favour the ester forming.
calcium is an element with atomic number20. Stating reason, answer each of the following questions:
i) Is calcium a metal or a non-metal?
ii) Will its atomic radius be larger or smaller than that of potassium with atomic number 19?
iii) Write the formula of its oxide.
An element 'M' with electronic configuration (2,8,2) combines separately with (NO3)-, (SO4)2-, and (PO4)3- radicals. Write the formula of the three compounds so formed. To which group and period of the Modern Periodic Table do the element 'M' belong? Will 'M' form covalent or ionic compounds ? Give a reason to justify your answer.
i) In which direction, towards the screen or away from the screen, does he move the lens?
ii) What happens to the size of the image? Does it decrease or increase?
iii) What happens to the image on the screen when he moves the object very close to the lens?