For the purpose of proper representation in this item, we let the number of moles of carbon in the compound be x, that of H is y. The equation of toluene now becomes,
CxHy
The combustion reaction is,
CxHy + O2 --> CO2 + H2O
The equation presented above may not be balanced yet. Then, we determine the number of mmols of C, H, and O in the product using the given masses.
(1) 8.20 mg CO2
(8.2 mg CO2)(1 mmol CO2/44 mg CO2) = 0.186 mmol CO2
which means,
0.186 mmol C
0.373 mmol O
(2) 1.92 mg H2O
(1.92 mg H2O)(1 mmol H2O/18 mg H2O) = 0.107 mmol H2O
which means
0.2133 mmol H
0.107 mmol O
Thus, the equation for toluene is,
C(0.186)H(0.2133)
Dividing the numbers by the lesser value,
CH(8/7)
To eliminate the fraction, we multiply by the denominator. Thus, the final answer would be,
<em> C7H8</em>
Answer:
(a) Hypoeutectic
(b) Alpha solid, aluminium
(c) 70% α
, 30% β
(d) 97.6% α, 2.4% β
(e) 97.6% α, 2.4% β
(f) 97% α, 3% β
Explanation:
(a) The eutectic composition for Al Si alloy is 11.7 wt% silicon, therefore, an Al-4% Si alloy is hypoeutectic
(b) For the hypoeutectic alloy, aluminium, Al, is expected to form first, such that the aluminium content is reduced till the point it gets to the eutectic proportion of 11.7 wt% silicon
(c) At 578°C we have
% α: Al (11 - 4)/(11 - 1) = 70% α
% L: Si 100 - 70 = 30% β
(d) At 576°C we have
α: 99.83% Si (99.83 - 4)/(99.83- 1.65) = 97.6% α
β: 1.65% Si (4 - 1.65)/(99.83- 1.65) = 2.4% β
(e) Primary α: 1.65% α (99.83 - 4)/(99.83 - 1.65) = 97.6% α
Eutectic 4% Si = 100 - 97.6 = 2.4% β
(f) At 25°C we have;
α%: (99.83 - 4)/(99.83 - 1) = 97% α
β%: 100 - 97 = 3% β.
Answer:
1000L
Explanation:
the 1 is a sig fig and since the 0 is between the 1 and 4 its also a significant number. to round them off you look at the 0,then look back at the 4 since its less than 5 u round down. then u replace the 43 with 0's
Answer:
Explanation:
13 ) symbol of enthalpy change = Δ H .
14 ) enthalpy change is nothing but heat absorbed or evolved .
During fusion enthalpy change
Δ H .= m Lf , m is mass and Ls is latent heat of fusion
During evaporation, enthalpy change
Δ H .= m Lv , m is mass and Lv is latent heat of evaporation
during temperature rise , enthalpy change
Δ H = m c Δ T
In case of gas , enthalpy change can be calculated by the following relation
Δ H = Δ E + W , Δ E is change in internal energy , W is work done by gas.
15 ) When enthalpy change is negative , that means heat is released to the environment .So reaction is called exothermic .
when heat is absorbed enthalpy change is positive . Reaction is endothermic.
Glucose and Galactose both have the same molecular formula, C6H12O6, but in the body, galactose must be first converted to glucose to make energy. The difference<span> is their </span>structures
