Answer:
Calcium
Explanation:
is a silver-gray metal which takes its name from the Latin word calx, which means lime. It is the fifth most abundant element in the earth's crust and is widely distributed as limestone (CaCO3), quicklime (CaO) and calcium fluoride.
This question can be simply solved by using heat formula,
Q = mCΔT
Q = heat energy (J)
m = Mass (kg)
C = Specific heat capacity (J / kg K)
ΔT = Temperature change (K)
when water freezes, it produces ice at 0°C (273 K)
hence the temperature change is 25 K (298 K - 273 K)
C for water is 4186 J / kg K or 4.186 J / g K
By applying the equation,
Q = 456 g x 4.186 J / g K x 25 K
= 47720.4 J
= 47.72 kJ
hence 47.72 kJ of heat energy should be removed.
Answer:
Rate of forward reaction will increase.
Explanation:
Effect of change in reaction condition on equilibrium is explained by Le Chatelier's principle. According to this principle,
If an equilibrium condition of a dynamic reversible reaction is disturbed by changing concentration, temperature, pressure, volume, etc, then reaction will move will in a direction which counteract the change.
In the given reaction,
A + B ⇌ C + D
If concentration of A is increase, then reaction will move in a direction which decreases the concentration of A to reestablish the equilibrium.
As concentration A decreases in forward direction, therefore, rate of forward reaction will increase.
As far as I know, the answer is B (breaking a rock)
