Answer: Option (b) is the correct answer.
Explanation:
It is given that mass of Mg is 97.22 g and it is known that molar mass of Mg is 24.305 g/mol.
So, calculate the number of moles as follows.
No. of moles = 
= 
= 4 mol
Also, it is known that 1 mole has 
atoms/mol. Therefore, calculate the number of atoms in 4 mol as follows.
= 
atoms
or, = 
atoms
Thus, we can conclude that there are atoms in 97.22 grams of Mg.
The heat that is required to raise the temperature of an object is calculated through the equation,
heat = mass x specific heat x (T2 - T1)
Specific heat is therefore calculated through the equation below,
specific heat = heat / (mass x (T2 - T1))
Substituting,
specific heat = 645 J / ((28.4 g)(15.5 - - 11.6))
The value of specific heat from above equation is 0.838 J/g°C.
The answer is Some of the heat used to make the steam is transformed into work as the steam pushes against the blades to make them turn. This also observes the law of conservation in thermodynamics. The kinetic energy in the steam helps push the blades and is converted to mechanical energy. Some of the energy is lost since it is never 100% efficient.
3.25 kg in g = 3.25 * 1000 = 3250 g
Molar mass C₂H₆O₂ = 62.0 g/mol
Mass solvent = 7.75 kg
Number of moles:
n = mass solute / molar mass
n = 3250 / 62.0
n = 52.419 moles
Molality = moles of solute / kilograms of solvent
M = 52.419 / 7.75
M = 6.7637 mol/kg
hope this helps!
M= #moles / L
4.35/.75 = 5.6
