Answer: The specific heat of the unknown metal is 
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

Q = Heat absorbed=
Joules
m= mass of substance = 86.8 g
c = specific heat capacity = ?
Initial temperature of the water =
Final temperature of the water =
Change in temperature ,
Putting in the values, we get:


The specific heat of the unknown metal is 
_Mg + _HCL = _MgCl2 + H2
Separate the terms on each side:
_Mg + _HCl = _MgCl2 + H2
Mg- 1 Mg-1
H-1 H-2
Cl-1 Cl-2
Mg is balanced on both sides so move on to the next (put a 1 in the space).
1Mg
There are two H's and two Cl's on the results side, so to balance the equation put a 2 as a coefficient for HCl and it'll all balance out.
2HCl
Balamced equation will be:
1Mg + 2HCL = 1MgCl2 + H2
True? If that’s what you are asking. It does decompose to that.
The answer is 27.92g . working is shown in the picture above.
Metal radiator. When hot water flows through the coils of the radiator , the metal heats up quickly by conduction and then radiates thermal energy into the surrounding air.
Answer: Metal radiator