Explanation:
Principal quantum number=n=7
Azimuthal quantum number=l:-
it is b forces hold matter together
A force is a push or pull on an object. Forces usually cannot be seen but their effects can. Nothing moves, changes speed, stops or changes direction without force. Heavier objects need more force to get them to move or change direction.
Answer:
The mechanical properties of urea formaldehyde resins may be improved by incorporating therein polyvinyl alcohol. The polyvinyl alcohol may be incorporated during pre-mixing, mid mixing, and/or post mixing of the resin components. Resins prepared using polyvinyl alcohol are particularly desirable in articles requiring improved mechanical strength and water resistance, as compared to similar resins prepared without the polyvinyl alcohol such as shingles.
Answer:
a Hg(NO3)2
b CoBr2,CoBr2·6H2O,CoBr2·2H2O
Explanation:
