<span>The enthalpy of fusion of the ice is 334 J/g. .... When ice at 0°C melts to liquid water at 0°C, it absorbs0.334 kJ of heat per gram. ... A 2 kg block of ice is placed in a container at 0 °C. How much energy is required to completely melt the block of ice? ... A 40.0 g block of ice at -15 degrees C is dropped into acalorimeter </span><span>
</span>
Answer:
Because if the object weighs more than the volume when it is placed in the water it will sink. If this object weighs less than the volume of water, it will float. This depends mostly on the type of item.
2H2 + O2 ---->2H2O
number of moles in reaction 2 mol 1 mol 2 mol
number of liters in the reaction 2*22.4 L 1*22.4 L 2*22.4L
We can see that volumes of the gases are proportional to coefficients in the reaction ( if gases are under the same conditions), so we can write
2H2 + O2 ---->2H2O
2 L 1 L 2 L
given 40 L ( 25 L) 40 L
We can see that we have excess of O2,
because if 2 L H2 are needed 1 L O2, then 40 L of H2 are needed 20 L O2.
So, limiting reactant is H2, and we will need to calculate Volume of H2O using H2.
2L H2 give 2L H2O(gas), so 40 L H2 give 40 L H2O.
Answer
RNA is single stranded
the balanced equation for the formation of ammonia is
N₂ + 3H₂ ---> 2NH₃
molar ratio of N₂ to NH₃ is 1:2
mass of N₂ reacted is 8.0 g
therefore number of N₂ moles reacted is - 8.0 g / 28 g/mol = 0.286 mol
according to the molar ratio,
1 mol of N₂ will react to give 2 mol of NH₃, assuming nitrogen is the limiting reactant
therefore 0.286 mol of N₂ should give - 2 x 0.286 mol = 0.572 mol of NH₃
therefore mass of NH₃ formed is - 0.572 mol x 17 g/mol = 9.72 g
a mass of 9.72 mol of NH₃ is formed
