Many nitrogen atoms have seven neutrons<span> (14-7 = 7). Some atoms of nitrogen, however, have eight electrons. They are atoms of N-15, an isotope of nitrogen. In a neutral atom, the number of protons must equal the number of electrons.</span>
The specific gravity of a sample is the ratio of the density of the sample with respect to one standard sample. The standard sample used in specific gravity calculation is water whose density is 1 g/mL. The solution having specific gravity 1.30 is the density of the sample that is 1.30 g/mL. Thus the weight of the 30 mL sample is (30×1.30) = 39 g.
Now the mass of the 10 mL of water is 10 g as density of water is 10 g/mL. Thus after addition the total mass of the solution is (39 + 10) = 49g and the volume is (30 + 10) = 40 mL. Thus the density of the mixture will be 
g/mL. Thus the specific gravity of the mixed sample will be 1.225 g/mL.
Data:
weight of water before heating = 0.349
weight of hydrate before heateing = 2.107
Formula:
Weight percent of water = [ (weight of water) / (weight of the hydrate) ] * 100
Solution:
Weight percent of water = [ 0.349 / 2.107] * 100 ≈ 16.6 %
Answer: 16.6%
The correct one is Respiratory Distress !!
As rest are not concerned with air pollution !!
Answer;
The partial negative charge on oxygen would stick out less and be less able to participate in hydrogen bonding.
Explanation;
Water is a polar molecule because the electrons are not shared equally, they're closer to the oxygen atom than the hydrogen.
-Normally, the water molecule is a bent shape because of the pair of lone electrons - they repulse each other and exert a compression to the hydrogen atoms at a slight 104º angle. It is a bent molecular geometry that results from tetrahedral electron pair geometry.
-The 2 lone electron pairs exerts a little extra repulsion on the two bonding hydrogen atoms to create a slight compression to a 104 degrees bond angle. Therefore, the water molecule is bent molecular geometry because the lone electron pairs.
Thus, If water were a linear molecule like co2, electrostatic interactions between water molecules would be much weaker, then the partial negative charge on oxygen would stick out less and be less able to participate in hydrogen bonding.
