Answer:
Check explanation
Explanation:
From the question, the parameters given are 64.7g of benzene,C6H6; a starting temperature of 41.9°C and bringing it to 33.2°C.
Molar mass of benzene,C6H6= 78.11236 g/mol.
Things to know: heat capacity of benzene, C6H6= 1.63 J/g.K, the heat of fusion = 9.87 kj/mol.
STEP ONE(1): ENERGY USED IN MELTING BENZENE SOLID.
Using the formula below;
Energy used in melting the solid(in JOULES) = (mass of benzene/molar mass of benzene) × heat of Fusion.
=(64.7 g of C6H6/ 78.11236(g per mol) of C6H6) × 9.87 kJ per mol.
= 8.175 J.
= 0.008175 kJ.
STEP TWO (2): ENERGY OF HEATING THE LIQUID.
It can be calculated from the formula below;
Energy= heat capacity (J/g.K) × mass of benzene× (∆T).
= 1.63 J/g.K × 64.7 × (41.9-33.2).
= 917.5J.
= 0.9175 kJ.
Energy required to boil benzene= Energy required to melt the bezene + energy required for boiling.
= 0.008175+ 0.9175.
= 0.93kJ
Approximately, 1 kJ
PH = −log [H+] = − log [5.4 × 10−3] ≈ 2.27 or 2.3.
or basically 2
Answer: Explanation:
Calcium (Ca), chemical element, one of the alkaline-earth metals of Group 2 (IIa) of the periodic table. It is the most abundant metallic element in the human body and the fifth most abundant element in Earth's crust.
...
Calcium.
atomic number 20
oxidation state +2
electron configuration 1s22s22p63s23p64s2
Explanation:
Answer:
Coefficient in front of the 
in the balanced equation - 4
Explanation:
The unbalanced reaction is shown below as:-
On the left hand side,
There are 1 nitrogen atom and 3 hydrogen atoms and 3 oxygen atoms
On the right hand side,
There are 1 nitrogen atom and 2 hydrogen atoms and 2 oxygen atoms
Thus,
Right side, 
must be multiplied by 6 and by 4
Left side, 
is multiplied by 5 and 
by 4 so to balance the whole reaction.
Thus, the balanced reaction is:-
<u>Coefficient in front of the in the balanced equation - 4</u>
