A: gold 19.32 g/ml
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To keep burning, fires require oxygen. Carbon dioxide is used in certain fire extinguishers to put out flames. Explanation: Because magnesium is higher on the reactivity scale than carbon, it is more reactive and eliminates oxygen from carbon dioxide (to give carbon and magnesium oxide).
Explanation:
The given data is as follows.
= 50 ml,
= 345 K
= 298 K,
= 317 K,
= 50 ml
Now, we will calculate the heat energy as follows.

= 
= 5857.6 J

= 
= 3974.8 J
As,
so there will be loss of heat. And, some heat will go to the calorimeter.
Hence, 

= 1882.8 J
We assume that the temperature of (calorimeter + water) is 298 K. Hence,
dT =
= (317 - 298) K
= 19 K
Hence, we will calculate the specific heat as follows.
C = 
= 
= 99.1 J/K
Thus, we can conclude that the value of
for the calorimeter is 99.1 J/K.