Answer: The correct answer is Option 1.
Explanation:
Control group is the group used in the experiment by the researchers in which no change in the variable is done. It is then set as a benchmark for the groups which are being tested.
We are given 4 groups which are being experimented for the flotation of an egg in water. As in Cup 1, there is no addition of salt and hence there is no change in the variables. So, this is set as a benchmark fro the cups which are further used in the experiment conducted.
Hence, the correct answer is Option 1.
Answer:
Only 
gives spontaneous reaction.
Explanation:
A redox reaction will be spontaneous if standard reduction potential (
) of the reaction is positive. Because it leads to negative standard gibbs free energy change (
), which is a thermodynamic condition for spontaneity of a reaction.
Where 
and 
represents standard reduction potential of reduction half cell and standard reduction potential of oxidation half cell.
(1) Oxidation: 
; 
Reduction: 
; 
So, 
Hence this pair will give spontaneous reaction.
(2) Similarly as above, 
Hence this pair will give non-spontaneous reaction.
(3) Similarly as above, 
Hence this pair will give non-spontaneous reaction.
(4) Similarly as above, 
Hence this pair will give non-spontaneous reaction.
Answer:
A scale, or a weight. Both of which are more scientifically referred to as a balance.
From Q = mcΔΤ, the specific heat capacity, c, of the metal that was cooled is c = Q/mΔT = (-769 J)/(46.4 g)(30.0 °C - 101.0 °C) = 0.233 J/g °C. From the table, it appears that this is the specific heat capacity of silver. So, the metal is most like silver.
Note: The value for Q was written as a negative value in the equation as heat energy was given off by the metal when the metal was cooled (from the metal’s point of view, it’s losing heat energy).
