All the elements in one group have the same number of valence electrons.
Photosynethesis, respiration, and combustion.
Solution :
It is given that :
The formula of the compound = 
And that 4.70 g of the sample contains 
mol of Br.
It means that :
1 mol of contains = 3 mol of Br
∴ 3 mol of 
contain in 1 mol of
mol of contains 
mol of
Thus the mol of = mol
The given mass is = 4.700 g
Therefore, the 
of 
= 298.4 g/mol
So of = of X + 3 x of Br
298.4 g/mol = of X + 3 x 79.90 g/mol
298.4 g/mol = of X + 239.7 g/mol
of X = 58.71 g/mol (since 1 amu = 1 g/mol)
Therefore the atomic mass of the unknown metal = 58.71 g/mol
So the unknown meta is Nickel.
0.01 cubic meters
Hope this helps
A small sample of methane burns, releasing 120.0 kJ of heat and doing 830.0 kJ of work. The total energy released is -950.0 kJ.
Energy is a property that is transferred to a physical system, recognizable in the performance of work and in the form of heat and light.
A small sample of methane undergoes combustion. As the hot gas mixture expands, it releases energy (E).
- It releases 120.0 kJ of heat. By convention, when heat is released, we assign it a negative sign. Thus, q = -120.0 kJ.
- It does 830.0 kJ of work. By convention, when the system does work on the surroundings, we assign it a negative sign. Thus, w = -830.0 kJ.
The change in the energy is the sum of the heat released and the work done.
ΔE = q + w = -120.0 kJ + (-830.0 kJ) = -950.0 kJ
A small sample of methane burns, releasing 120.0 kJ of heat and doing 830.0 kJ of work. The total energy released is -950.0 kJ.
Learn more about energy here: brainly.com/question/13881533
