You'll want to add three amounts of heat.
(1) Specific heat of lowering the temperature from -135°C to the melting point -114°C
(2) Latent heat of fusion/melting
(3) Specific heat of elevating the temperature from -114°C to -50°C
(1) E = mCΔT = (25 g)(0.97 J/g·°C)(1 kJ/1000 J)(-114 - -135) = 0.509 kJ
(2) E = mΔH = (25 g)(5.02 kJ/mol)(1 mol/46.07 g ethanol) = 2.724 kJ
(3) E = mCΔT = (25 g)(2.3 J/g·°C)(1 kJ/1000 J)(-50 - -114) = 3.68 kJ
<em>Summing up all energies, the answer is 6.913 kJ.</em>
Answer:
1.52atm is the pressure of the gas
Explanation:
To solve this question we must use the general gas law:
PV = nRT
<em>Where P is pressure in atm = Our incognite</em>
<em>V is volume = 50.5L</em>
<em>n are moles of gas = 3.25moles</em>
<em>R is gas constat = 0.082atmL/molK</em>
<em>And T is absolute temperature = 288.6K</em>
To solve pressure:
P = nRT / V
P = 3.25mol*0.082atmL/molK*288.6K / 50.5L
P = 1.52atm is the pressure of the gas
These are called resistors.
To minimize the sharp pH shift that occurs when a strong acid is added to a solution, IT IS PRACTICAL TO ADD A WEAK BASE.
When a strong acid is added to a solution, it usually brings about a sharp change in the pH of the concerned solution. To avoid this, one can add a weak base to the solution first. The weak base will serves as a buffer for the strong acid and prevents the solution from experiencing sharp pH variations.