Answer:
False.
This is false because, no chemical reaction could possibly happen.
But in case of sodium it is highly reactive with water.......... so there will be a chemical reaction.
but as sodium is not a insoluble molecular compound this is not applicable to the situation.
Answer:
a. ΔH⁸ = -1420 kJ/mol b. ΔH⁸ = -1144.84 kJ/mol
Explanation:
a.
C₂H₄ (g) + 3 O₂ (g) ------------------------ 4 CO₂ (g) + 2 H₂O (l) ΔH⁸ = ?
ΔH⁸f kJmol 52.47 0 -399.5 -285.83
ΔH⁸ = 2(-399.5) + 2 (-285.83) - (52.47)
ΔH⁸ = -1420 kJ/mol
b.
H₂S (g) + 3 O₂ (g) ---------------------- 2 H₂O (l) + 2 SO₂ (g)
ΔH⁸f kJmol -20.50 0 -285.83 -296.84
ΔH⁸ = 2(-285.83) + 2 (-296.84) - (-20.50)
ΔH⁸ = -1144.84 kJ/mol
Answer:
Acceleration is :
a = 2.89 m/s2
Explanation:
Acceleration : It is the change in the velocity of the object per unit time.
The object starts from the rest , so the initial velocity of the object is zero.
Initial velocity , u = 0
Final velocity = 100 km/h
Change the velocity to m/s because[ time unit is in second(9.60 s)]
1 km = 1000 m
1 hour = 60 x 60 sec = 3600 sec
v = 27.78 m/s
u = 0 m/s
time = 9.60 s
The acceleration"a" is calculated using :
2Cu + S = Cu₂S
n(Cu)=m(Cu)/M(Cu)
n(Cu)=12.71/63.55=0.2 mol
n(S)=m(s)/M(S)
n(S)=8.000/32.01=0.25 mol
Cu:S 2:1
0.2 mol : 0.25 mol copper deficiency, sulphur in excess
theoretical mass of copper (I) sulfide
m(Cu₂S)=M(Cu₂S)n(Cu)/2
the percentage yield in the reaction is
w=m'(Cu₂S)/m(Cu₂S)=2m'(Cu₂S)/M(Cu₂S)n(Cu)
w=2*14.72/(159.16*0.2)=0.925 (92.5%)
