Answer:
Explanation:
Bones?
Bones are primarily made of calcium. Also, they protect the body, which is pretty much obvious. They also act as camouflage.
The only but I have is, can they be found as a filler in most household?
Asides that, bones pretty much fits in to the answer.
Answer:
1.29 kg
Explanation:
As we know that
W= FS
1.56 = F (0.78)
F= 1.56/0.78
F= 2 N
Now, According to the definition of Force
F= ma
then
m= F /a
m= 2 / 1.54
m = 1.29 kg
I believe the answer is C
Hope this helps :)
Answer : The change in enthalpy of the reaction is, -310 kJ
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given main reaction is,

The intermediate balanced chemical reaction will be,
(1)

(2)

(3)

Now we will reverse the reaction 1 and multiply reaction 1 by 2, reaction 2 by 2 and reaction 3 by 3 then adding all the equations, we get :
(1)

(2)

(3)

The expression for enthalpy of formation of
will be,



Therefore, the change in enthalpy of the reaction is, -310 kJ