No of Neutrons =Mass No-No of protons


- Hence it has atomic no 38
The element is Stroncium(Sr)
Ca(NO3)2 -------> Ca²⁺ +2NO3⁻
M(Ca(NO3)2)= M(Ca) + M(N) + 6M(O)= 40.0 +14.0 +6*16.0 = 150 g/mol
15.0 g Ca(NO3)2 * 1mol/150 g = 0. 100 mol Ca(NO3)2
Ca(NO3)2 -------> Ca²⁺ +2NO3⁻
1 mol 2 mol
0.100 mol 0.200 mol
We have 0.2 mol NO3⁻ in 300. mL=0.300 L of solution,
so
0.200 mol NO3⁻ / 0.300 L solution ≈ 0.667 mol NO3⁻ /L solution = 0.667 M
Concentration of NO3⁻ is 0.667 M.
The air in the sky and the clouds are gas, however some things in the sky [such as the sun/moon] are solid.
Hope that helped!
Gases have high kinetic energy: the molecules are moving much more than in a liquid or solid. You can cut out A and B. In the liquids, the difference is temperature. If a lower temperature is closer to being solid, and a solid has lower kinetic energy than a liquid, then C is the answer. Hope this helps.
Hydrogen bonds are a strong attractive force, since they are less stronger than ionic bonds.