You could write about a fear you may have had as a child, eg. the dark, or underneath the bed, etc...
The answer iiiis... A: Group 8A, Period 1
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Here's why:</h3>
The way I found this doesn't have much thought or explanation--I just remember that helium and hydrogen are in period 1. The only answer choice with "period 1" is A.
Answer : The metal used was iron (the specific heat capacity is 
).
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.
where,
= specific heat of unknown metal = ?
= specific heat of water = 
= mass of unknown metal = 150 g
= mass of water = 200 g
= final temperature of water = 
= initial temperature of unknown metal = 
= initial temperature of water = 
Now put all the given values in the above formula, we get
Form the value of specific heat of unknown metal, we conclude that the metal used in this was iron (Fe).
Therefore, the metal used was iron (the specific heat capacity is ).
At Equilibrium, The rate of formation of Products is equal to the rate of degradation of Reactants.
Hope this helps!
