Answer:
B.Thermal insulation minimizes energy loses to the atmosphere.
Explanation:
It is important because it helps to stop hit from transferring from the calorimeter to the environment. This would help to have an accurate measurement of the heat that was used in the chemical process. The greatest cause of error that happens in calorimetry is when heat is lost to the environment. To reduce this, you insulate the calorimeter and add a cover.
Answer:
Our Sun (a star) and all the planets around it are part of a galaxy known as the Milky Way Galaxy.
The loss of electron from an results in the formation of cation represented by the positive charge on the element whereas gaining of electron results in the formation of anion represented by the negative charge on the element.
The alkali earth metal beryllium (
) belongs to the second group of the periodic table. The ground state electronic configuration of
is:
From the electronic configuration it is clear that it has 2 valence electrons in its valence shell (
).
After losing all valence electrons that is 2 electrons from
orbital. The electronic configuration will be:

Since, lose of electron is represented by positive charge on the element symbol. So, the beryllium will have +2 charge on its symbol as
.
Hence, beryllium will have 2+ charge on it after losing all its valence electrons in the chemical reaction.
Answer:
-12.5 kJ/mol
Explanation:
The free-energy predicts if a reaction is spontaneous or not. If it is, ΔG < 0. When a reaction happens by steps, the free-energy of the global reaction can be calculated by the sum of the free-energy of the steps (Hess law). If it's needed to operations at the reaction the same operation must be done in the value of ΔG (if the reaction is inverted, the signal of ΔG must be inverted).
Phosphocreatine → creatine + Pi ∆G'° = –43.0 kJ/mol
ATP → ADP + Pi ∆G'° = –30.5 kJ/mol (x-1)
--------------------------------------------------------------------------------------
Phosphocreatine → creatine + Pi ∆G'° = –43.0 kJ/mol
Pi + ADP → ATP ∆G'° = 30.5 kJ/mol
The bold compounds are in opposite sides, so they'll be canceled in the sum of the reactions:
Phosphocreatine + ADP → creatine + ATP
∆G'° = -43.0 + 30.5
∆G'° = -12.5 kJ/mol
Answer:
9 moles of NaNO3 is obtained
Explanation:
The balanced chemical reaction equation for the reaction is;
Al(NO3)3 + 3NaCl-------> 3NaNO3 + AlCl3
Now, we have to determine the limiting reactant. The limiting reactant yields the least amount of NaNO3.
1 mole of Al(NO3)3 yields 3 moles of NaNO3
4 moles of Al(NO3)3 yields 4 * 3/1 = 12 moles of NaNO3
Also,
3 moles of NaCl yields 3 moles of NaNO3
9 moles of NaCl yields 9 * 3/3 = 9 moles of NaNO3
Hence, NaCl is the limiting reactant and 9 moles of NaNO3 is obtained.