The coefficient of heat conductivity of heat-insulating materials does not exceed _____

Which of the following is not a property of a good electrical insulator?

Which of the following is not true about cork?

Nitrocellulose glues are prepared from _____

It results in the failure of concrete made from the cement if the amount of alkali oxides in it exceeds _____

Clay predominates in calcareous materials while calcium carbonate predominates in argillaceous materials.

Portland cement was invented by _______

Expanding cement is obtained by the addition of an expanding medium like _____ to the ordinary cement.