Glass has more than three times larger thermal conductivity than ...

[genevieve1028]

Glass has more than three times larger thermal conductivity than air. Yet glass-wool (glass fibers and air) is preferable to insulate wall spaces rather than leaving empty air spaces.
 
  Why is glass-wool better although glass has larger conductivity than air?

Question 2

When Venus first formed it had large quantities of water vapor in its atmosphere while today only very low levels of water are present. Where did most of the water vapor go?
 
  A) it was destroyed in the atmosphere by ultraviolet light from the Sun
  B) it became chemically incorporated into rocks in the crust
  C) it was blasted into space by impacts
  D) it escaped into space

[momtoalll]

Answer to Question 1

Convection is very important, and the glass fibers reduce the convecting air currents.

Answer to Question 2

A

[genevieve1028]

Excellent

[tranoy]

Gracias!