Answer:
a. Endothermic
b. 26.37kJ/mol
Explanation:
a. As we can see, the temperature of the water is decreasing when the reaction is occurring, that means the reaction is absorbing heat and is endothermic
b. To find the enthalpy we must find the change in heat when 12.1g of KCl are dissolved. Using the equation:
Q = -m*ΔT*C
<em>Where Q is change in heat</em>
<em>m the mass of solution (250g + 12.1g = 262.1g)</em>
<em>ΔT is change in heat (17.1°C - 21.0°C = -3.9°C)</em>
<em>And C is specific heat of the solution (4.184J/g°C assuming is the same than the specific heat of water).</em>
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Replacing:
Q = -262.1g*-3.9°C*4.184J/g°C
Q = 4277J = 4.28kJ
As reaction enthalpy is the change in heat per mole of reaction, we must find the moles of 12.1g of KCl:
<em>Moles KCl -Molar mass: 74.55g/mol-:</em>
12.1g KCl * (1 mol / 74.55g) = 0.1623 moles KCl
The reaction enthalpy us:
4.28kJ / 0.1623mol = }
<h3>26.37kJ/mol</h3>
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3rd: Every action has an equal and opposite reaction. So the third law basically says that if you shoot out stuff in one direction you will move in the other direction. This is howrockets work in a vacuum. They have a source of fuel which is heated up so that it expands and is pushed out of the rocket.
Hope this helps a little... ^^
To lower the amount of trash my family produces, we can use reusable bottles, cutlery, and dishes. This would be a better alternative to using both paper, and plastic items which would increase trash output. Reusable items like dishes can be used multiple times without throwing them away, instead of having to use plastic items that we’d throw away after using once.
Given a sample of three unknown solids, we would be able to deduce which are ionic solids by their melting and boiling points, conductivity in water, and the insulation they provide.
<h3>What are Ionic solids?</h3>
- An ionic solid is a solid formed by ionic bonds.
- They are the solid version of ionic compounds, which are held together by strong electrostatic energies.
<h3>What properties do they possess?</h3>
- Among their many properties, ionic solids possess high melting and boiling points.
- These solids are also known to conduct electricity well <em><u>when </u></em><em><u>dissolved </u></em><em><u>into </u></em><em><u>water</u></em>, however, this can be tested after melting them as they <u>will not conduct electricity in a solid state</u>.
- A final property that we can use to identify them is that they provide a good means of insulation.
- Each of these properties can be tested and will allow us to determine the ionic solids amongst the samples.
Therefore, we can find the ionic solids amongst the samples by testing their melting and boiling points, conductivity in water, and the insulation they provide, given that each of these should provide high values to indicate an ionic solid.
To learn more about ionic solids visit:
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