Answer:fH = - 3,255.7 kJ/mol
Explanation:Because the bomb calorimeter is adiabatic (q =0), there'is no heat inside or outside it, so the heat flow from the combustion plus the heat flow of the system (bomb, water, and the contents) must be 0.
Qsystem + Qcombustion = 0
Qsystem = heat capacity*ΔT
10000*(25.000 - 20.826) + Qc = 0
Qcombustion = - 41,740 J = - 41.74 kJ
So, the enthaply of formation of benzene (fH) at 298.15 K (25.000 ºC) is the heat of the combustion, divided by the number of moles of it. The molar mass od benzene is: 6x12 g/mol of C + 6x1 g/mol of H = 78 g/mol, and:
n = mass/molar mass = 1/ 78
n = 0.01282 mol
fH = -41.74/0.01282
fH = - 3,255.7 kJ/mol
Answer: Substance is Mercury (Hg)
number of protons = 80
number of electrons = 80
Explanation:
Atomic number which is symbolized by "Z" is the number of protons in nucleus of an atom.
Hence,
number of protons = atomic number = 80
- By knowing atomic number, we can find the element by using periodic table. Since the atomic number 80, the element is Mercury (Hg).
If the substance is in its neutral state, which means there is no charge on it, then the number of protons equals to the number of electrons of that element.
Hence,
number of electrons = number of protons = 80
MgSO4, CO2, AlCl3 are the answer
Question:
Which subscripts complete the chemical formula for the compound?
Answer:
A: 3
B: 8
