The heat content of a system is its enthalpy!
Answer:
C, A, D and B
Explanation:
Water evaporates from the surface of the oceans leaving behind salts. As water vapor rises, it collects and is stored in clouds.
As water cools in the clouds, condensation occurs. Condensation is when gases turn back into liquids.
Condensation creates precipitation. Precipitation includes rain, snow, hail and sleet. The precipitation allows the water to return again to the Earth's surface.
When precipitation lands on land, the water can sink into the ground to become part of our underground water reserves, also known as groundwater.
First find the molar masses of all of the compounds:
SrCl2 = 158.53g/mol
SrI2 = 341.43g/mol
SrO = 103.62g/mol
SrS = 119.68g/mo
Then find the molar mass of Sr in each of the compounds. Since there is only one Sr in every compound, the mass will be the same: 87.62g/mol Sr
Now divide the molar mass of Sr by each of compounds' masses:
SrCl2 = (87.62)/(158.53) = 0.553
SrI2 = (87.62)/(341.43) = 0.257
SrO = (87.62)/(103.62) = 0.846
SrS = (87.62)/(119.68) = 0.732
Now multiply each of the results by 100 to get the percent composition of Sr by mass:
(0.553)(100) = 55.3% Sr in SrCl2
(0.257)(100) = 25.7% Sr in SrI2
(0.846)(100) = 84.6% Sr in SrO
(0.732)(100) = 73.2% Sr in SrS
Thus SrO has the highest percent composition by mass of Sr