Answer:
<em> 14, 508J/K</em>
ΔHrxn =q/n
where q = heat absorbed and n = moles
Explanation:
<em>m = mass of substance (g) = 0.1184g</em>
1 mole of Mg - 24g
<em>n</em> moles - 0.1184g
<em>n = 0.0049 moles.</em>
Also, q = m × c × ΔT
<em> Heat Capacity, C of MgCl2 = 71.09 J/(mol K)</em>
<em>∴ specific heat c of MgCL2 = 71.09/0.0049 (from the formula c = C/n)</em>
<em>= 14, 508 J/K/kg</em>
ΔT= (final - initial) temp = 38.3 - 27.2
= 11.1 °C.
mass of MgCl2 = 95.211 × 0.1184 = 11.27
⇒ q = 11.27g × 11.1 °C × <em>14, 508 j/K/kg </em>
<em>= 1,7117.7472 J °C-1 g-1</em>
<em />
<em>∴ ΔHrxn = q/n</em>
<em>=1,7117.7472 ÷ 0.1184 </em>
<em>= 14, 508J/K</em>
Answer:
The energy released will be -94.56 kJ or -94.6 kJ.
Explanation:
The molar mass of methane is 16g/mol
The given reaction is:
the enthalpy of reaction is given as ΔH = -890.0 kJ
This means that when one mole of methane undergoes combustion it gives this much of energy.
Now as given that the amount of methane combusted = 1.70g
The energy released will be:
Toulene = 35.6 g
Benzene = 125 g = 0.125 kg
Molecular weight of Toluene C6H5CH3 = 92.1g/mol
Moles of toulene = 35.6 g / 92.1 g/mol = 0.3865 mol
Now the molarity of the toulene in the given solution = 0.3865 / 0.125 = 3.092 m
Molarity of C6H5CH3 = 3.092 m
18 D
19 B
20 D
21 Anabolic steroid abuse can lead to kidney and liver failure, enlarged heart or high blood pressure and changes in blood cholesterol.
<span>Passive transport is a movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy input.</span>
