Answer:
We take 20.0 mL of the 1.0 M fruit drink solution and then add 80.0 mL of water to make 100 mL of a 0.2 M fruit drink solution.
Explanation:
- Using the rule that: the no. of millimoles of a solution before dilution is equal to the no. of millimoles of the solution after the dilution.
<em>(MV) before dilution = (MV) after dilution.</em>
M before dilution = 1.0 M, V before dilution = ??? mL.
M after dilution = 0.2 M, V after dilution = 100 mL.
<em>∴ V before dilution = (MV) after dilution / M before dilution </em>= (0.2 M)(100 mL) / (1.0 M) = <em>20.0 mL.</em>
<em>So, we take 20.0 mL of the 1.0 M fruit drink solution and then add 80.0 mL of water to make 100 mL of a 0.2 M fruit drink solution.</em>
Answer : The enthalpy of the reaction = -1839.6 KJ
Solution : Given,
= -520.0 KJ/mole
= -1699.8 KJ/mole
The balanced chemical reaction is,

Formula used :


We know that the standard enthalpy of formation of the element is equal to Zero.
Therefore, the enthalpy of formation of (Mn) and (Al) is equal to zero.
Now, put all the values in above formula, we get
![\Delta (H_{f})_{reaction}=[2moles\times (-1699.8 KJ/mole)}+3moles\times (0\text{ KJ/mole}})]-[(3moles\times(-520.0KJ/mole }+4moles\times(0\text{ KJ/mole})]](https://tex.z-dn.net/?f=%5CDelta%20%28H_%7Bf%7D%29_%7Breaction%7D%3D%5B2moles%5Ctimes%20%28-1699.8%20KJ%2Fmole%29%7D%2B3moles%5Ctimes%20%280%5Ctext%7B%20KJ%2Fmole%7D%7D%29%5D-%5B%283moles%5Ctimes%28-520.0KJ%2Fmole%20%7D%2B4moles%5Ctimes%280%5Ctext%7B%20KJ%2Fmole%7D%29%5D)
= (-3399.6) + (1560)
= -1839.6 KJ
Answer:
Nitrogen molecule is 28 neuclons×1.67×10-27 kg/nucleon = 4.68 д 10-26 kg. So the average speed of a gas molecule is about 500 m/sec. This is roughly the speed of sound in a gas 340 m/sec. So the average kinetic energy of the gas molecules is related to the temperature of the gas.
I hope this is helpful