Answer:
15. 2.66 moles .
16. 2.09L.
Explanation:
Molarity of a solution is simply defined as the mole of solute per unit litre of the solvent. Mathematically, it is represented as:
Molarity = mole /Volume.
With the above formula, let us answer the questions given above
15. Data obtained from the question include the following:
Volume of solution = 1.4L
Molarity = 1.9M
Mole of solute =.?
Molarity = mole /Volume
1.9 = mole / 1.4
Cross multiply
Mole = 1.9 x 1.4
Mole = 2.66 moles
Therefore, the mole of the solute present in the solution is 2.66 moles.
16. Data obtained from the question include the following:
Mole of solute = 0.46 mole
Molarity = 0.22M
Volume of solvent (water) =.?
Molarity = mole /Volume
0.22 = 0.46/Volume
Cross multiply
0.22 x Volume = 0.46
Divide both side 0.22
Volume = 0.46/0.22
Volume = 2.09L
Therefore, 2.09L of water is required.
The final temperature = 36 °C
<h3>Further explanation</h3>
The balanced combustion reaction for C₆H₆
2C₆H₆(l)+15O₂(g)⇒ 12CO₂(g)+6H₂O(l) +6542 kJ
MW C₆H₆ : 78.11 g/mol
mol C₆H₆ :

Heat released for 2 mol C₆H₆ =6542 kJ, so for 1 mol

Heat transferred to water :
Q=m.c.ΔT

Answer: This would be considered concentrated because if you're upping the recipe on your own accord, it would be way more sour, causing the lemonade to be more concentrated. It would be diluted if you added less than 2 lemons.
Answer:
This question is somehow not clear, because a typical human eye can notice objects which have wavelengths from about 380 to 740 nanometers. This is called visible spectrum (the portion of the electromagnetic spectrum that is visible to the human eye). Electromagnetic radiation in this range of wavelengths is called visible light or simply light.
Someone even can see extra colors - they able to see beyond the visible spectrum. The reason that the human eye can see the spectrum is because those specific wavelengths stimulate the retina in the human eye. The human retina can only detect incident light that falls in waves from about 380 to 740 nanometers long, so we can’t see microwave or ultraviolet wavelengths. This also applies to infrared lights which has wavelengths longer than visible and shorter than microwaves, thus being invisible to the human eye.
In conclusion, the human eye can not notice that objects with wavelength not in the range of 380 to 740 nanometers.
Explanation: