Answer:
- <u><em>Sodium fluoride</em></u>
Explanation:
A <em>solution </em>is constituted by two parts: the solute and the solvent (there may be more than 1 solute and more than 1 solvent, but that is not the key of the answer).
<em>Solute</em> is the substace that is dissolved and it is in less amount than the solvent.
<em>Solvent</em> is the substance that can dissolve the solute and it is a greater amount than the solute.
In the given solution:
- <em>sodium fluoride</em>, <em>85.0 mL</em>, is the solute,
- <em>water</em>, <em>350.0 mL</em> is the solvent, and
- the mixture of both substances is the solution.
First find the mass of <span>solute:
Molar mass KNO</span>₃ = <span>101.1032 g/mol
mass = Molarity * molar mass * volume
mass = 0.800 * 101.1032 * 2.5
mass = 202.2064 g of KNO</span>₃
<span>To prepare 2.5 L (0800 M) of KNO3 solution, must weigh 202.2064 g of salt, dissolve in a Beker, transfer with the help of a funnel of transfer to a volumetric flask, complete with water up to the mark, capping the balloon and finally shake the solution to mix.</span>
hope this helps!
Answer:
mixture
Explanation:
The properties of the components of substance are different. One component has magnetic properties, another does not. So, we have at least 2 individual substances that were mixed together. So, we have a mixture.
Here we have to choose the challenge which is faced by the scientist to make a hydrogen fuel cell by using water.
The challenge that the scientists are facing a. decomposition of water requires a high energy.
For the generation of fuel cells by hydrogen the use of water (H₂O) is a challenging task as the H-O bond in water is so strong and need high activation energy.
As per the mechanism of hydrogen fuel cell generation of H₂ is compulsory. Water remains in its solution as H₂O⇔H⁺ + OH⁻. The breaking of hydroxide ion (OH⁻) to form free hydrogen need a high energy, which cannot meet easily by any energy source.
The sun is always a renewable energy source as the energy of sun is infinitive.
The decomposition of water will only produce oxygen (O₂) and hydrogen (H₂) among which H₂ will be used in the fuel cell and O₂ is not at all harmful.
The excess O₂ is always good for the environment as it is the breathing source in the living system.
