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Answer:
They are called insulators
Answer:
Elements in the same group have the same number of valence electrons.
Explanation: Science.
<span>The student should
follow following steps to make 1 L of </span>2.0 M CaCl₂.<span>
<span>
1. First he should
calculate the number of moles of 2.0 M CaCl</span></span>₂ in 1 L solution.<span>
</span>Molarity of the solution = 2.0 M<span>
Volume of solution which should be prepared = 1 L
Molarity =
number of moles / volume of the solution
Hence, number of moles in 1 L = 2 mol
2. Find
out the mass of dry CaCl</span>₂ in 2 moles.<span>
moles =
mass / molar mass
Moles of CaCl₂ =
2 mol</span><span>
Molar mass of CaCl₂ = </span><span>110.98 g/mol
Hence, mass of CaCl</span>₂ = 2 mol x <span>110.98 g/mol
= 221.96
g
3. Weigh the mass
accurately
4. Then take a cleaned and dry1 L volumetric flask and place a funnel top of it. Then carefully add the salt into the volumetric flask and
finally wash the funnel and watch glass
with de-ionized water. That water also should be added into the volumetric
flask.
5. Then add some
de-ionized water into
the volumetric flask and swirl well until all salt are
dissolved.
<span>6. Then top up to
mark of the volumetric flask carefully.
</span></span>
7. As the final step prepared solution should be labelled.
Explanation:
When we add a non-volatile solute in a solvent then due to the impurity added to the solution there will occur an increase in the boiling point of the solution.
This increase in boiling point will be known as elevation in boiling point.
As one beaker contains seawater (water having NaCl) will have some impurity in it. So, more temperature is required by seawater to escape into the atmosphere.
Whereas another beaker has only pure water so it is able to easily escape into the atmosphere since, it contains no impurity.
Thus, we can conclude that level of pure water will decrease more due to non-volatile solute present in it as compared to seawater.
