Its D. combustibillaty
A. density is how hard or densely the substances molecules are together
B.boiling point is the point at which bonds that hold molecules are broken and so the substances boils
C. malleability is how easily a substance can be stretched until it breaks
D. is a chemical property of how much chemical energy is stored in a substance for it to combust
hope that helps
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Answer:
a
They form an ionic bond by exchanging two electrons.
Explanation:
Magnesium loses two electrons and oxygen gains these electrons so ionic bond is formed
Answer:
it is a base because they accept H+ ions
Explanation:
Based on the information I would assume B, 73 degrees...
It shouldn't be A, 4 minutes on the burner should increase the temperature.
If it were D, it would be beyond boiling, and water takes a decent amount of energy to heat, D should be all vapor.
Same logic for C, it's basically almost boiling.
I would say 73 degrees seems most reasonable for 4 minutes.
Answer: 
Explanation:
Electron gain enthalpy is defined as energy released on addition of electron to an isolated gaseous atom.
The amount of energy released will be maximum when the tendency to attract electrons is maximum. As flourine has atomic number of 9 and has electronic configuration of 2,7. It can readily gain 1 electron to attain stable noble gas configuration and hence liberates maximum energy.