Answer:
- <em>Hydration number:</em> 4
Explanation:
<u>1) Mass of water in the hydrated compound</u>
Mass of water = Mass of the hydrated sample - mass of the dehydrated compound
Mass of water = 30.7 g - 22.9 g = 7.8 g
<u>2) Number of moles of water</u>
- Number of moles = mass in grams / molar mass
- molar mass of H₂O = 2×1.008 g/mol + 15.999 g*mol = 18.015 g/mol
- Number of moles of H₂O = 7.9 g / 18.015 g/mol = 0.439 mol
<u>3) Number of moles of Strontium nitrate dehydrated, Sr (NO₃)₂</u>
- The mass of strontium nitrate dehydrated is the constant mass obtained after heating = 22.9 g
- Molar mass of Sr (NO₃)₂ : 211.63 g/mol (you can obtain it from a internet or calculate using the atomic masses of each element from a periodic table).
- Number of moles of Sr (NO₃)₂ = 22.9 g / 211.63 g/mol = 0.108 mol
<u>4) Ratio</u>
- 0.439 mol H₂O / 0.108 mol Sr(NO₃)₂ ≈ 4 mol H₂O : 1 mol Sr (NO₃)₂
Which means that the hydration number is 4.
Answer:
1. water will freeze at a temperature below 32 degrees fahrenheit 0 degree celsius.
2. Ice will melt at a temperature above 32 degrees fahrenheit 0 degrees celsius.
3. water boils at 212 degrees fahrenheit or 100 degrees celsius.
Answer:

Explanation:
First of all we need to calculate the heat that the water in the cooler is able to release:

Where:
- Cp is the mass heat capacity of water
- V is the volume
is the density


To calculate the mass of CO2 that sublimes:

Knowing that the enthalpy of sublimation for the CO2 is: 


The atoms and molecules in gases<span> are much more spread out than in solids or</span>liquids<span>. They vibrate and move freely at high speeds. A </span>gas<span> will fill any container, but if the container is not sealed, the </span>gas<span> will escape. </span>Gas<span> can be compressed much more easily than a </span>liquid<span> or solid</span>