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.
Natural selection requires variation between individuals. Mutations and reproduction increase genetic variation in a population. Natural selection occurs when environmental pressures favor certain traits that are passed on to offspring.
No. When water first begins to cool down, it contracts. However, as it gets colder and eventually freezes, it begins to expand.
You can test this by freezing water in a water bottle: when you take it out of the freezer, the cap might have popped off or cracks may have formed in the sides of the bottle.
Answer: Water expands when frozen, not contracts.
The number of moles in each sample will be 0.391 moles, 30.7 moles, 0.456 moles, and 1350 moles
<h3>What is the number of moles?</h3>
The number of moles of a substance is the ratio of the mass of the substance to the molar mass.
In other words; mole = mass/molar mass.
Thus:
- moles of 18.0 g
= 18.0/46
= 0.391 moles
- moles of 1.35 kg
= 1350/44
= 30.7 moles
- moles of 46.1 g
= 46.1/101.1
= 0.456 moles
- moles of 191.8 kg
= 191800/142
= 1350 moles
More on the number of moles of substances can be found here: brainly.com/question/1445383
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