Answer:
A
Explanation:
the tendency of a material to conduct heat or electricity can be detected on the outside
Answer: Hydrogen and helium
Explanation:
Answer:
C. some substances can move freely across the cell membrane, while others must be transported.
Explanation:
Answer:
Ammonia contains an asymmetrical distribution of electric charge.
Explanation:
Hello there!
In this case, accordingly to the electronegativity difference we can calculate for the N-H bond, and based off our periodic table, which shows an electronegativity of 3.0 and 2.1 for N and H respectively, we obtain:

Which is within the range of polar molecule even the both of them are nonmetals. Thus, choices a and b are firstly discarded; nonetheless, even when they are both nonmetals, two of these elements usually have a nonpolar bond, which means that option C is discarded, and therefore, our answer is ammonia contains an asymmetrical distribution of electric charge.
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It splits into two equal nuclei of approx. equal mass.