Okay
Mr (H2O)= 18g
therefore moles of H2O
is 720.8/18= 40.04mol
the ratio of H2 to O2 to H2O is
2 : 1 : 2
so moles of H2 is same as H2O here
H2= 40.04moles
moles of O2 is half
so 40.04 x 0.5
20.02moles
grams of O2 is
its moles into Mr of O2
that's 20.02 x 32 = 640.64g
Answer:
2
Explanation:
1. The dew is formed when the water vapor at the atmosphere contacts the leaves, which are at a low temperature, so, the vapor temperature decreases, and the liquid is formed. So, it's a gas to liquid change.
2. Ice cubes are at the solid-state, thus this transformation is solid to a liquid change.
3. The cold juice is at a low temperature, so when the water vapor of the air contacts with the glass, its temperature decreases, and its change to a liquid phase. So, it's a gas to liquid change.
4. The evaporated water from the Earth's surface goes to the atmosphere, and, at high altitudes, the temperature is low, so the water vapor condenses and the drops get closer together forming the clouds. So, it's a gas to a liquid change.
B. released, forming bonds usually releases energy.
A. Oxygen. Oxygen has an atomic mass of 16. The atomic mass of an atom is the combined weight o the protons and neutrons. Since Oxygen's atomic mass is 16, it has 8 protons and 8 neutrons.
