18. c
19. A
20. decomposition reaction
21. 4
22. 0.04%
Answer:
The answer to your question is: letter A.
Explanation:
A Covalent bond polar is between 2 non metals where one atom is bigger than the other one so the distribution of charges creates this polarity.
A. One atom attracts shared electrons more strongly than the other atom This is the correct definition of bond polar, one element is bigger and stronger than the other element.
B. One atom has transferred its electrons completely to another atom This definition is incorrect, it is the definition of ionic bonding.
C. A sea of electrons has been created between the elements This definition is incorrect for the polar bond, it describes a metallic bonding.
D. Two atoms are sharing electrons with equal attraction This definition is incorrect for a polar bond, but is the correct definition for nonpolar bonding.
If we dissolve salt in water they will reduce the intermolecular forces between water molecule and this will decrease the surface tension.
Surface tension is due to cohesive forces (the forces between molecules of same substance) hence as cohesive forces decreases the surface tension also decreases
Answer
:
Flammable substances
Explanation
:
<em>Flammable substances</em> will catch fire and continue to burn when they contact an ignition source like a spark or a flame.
For example, <em>methanol</em> is a flammable liquid.
A flammable solid may also catch fire through friction. <em>Matches</em> are flammable solids.
Hydrophobic molecules tend to be nonpolar molecules that group together to form micelles rather than be exposed to water. Hydrophobic molecules typically dissolve in nonpolar solvents (e.g., organic solvents).