Answer:
The boiling point decreases as the volume decreases.
Explanation:
The Temperature - Volume law otherwise called as Charles law is applied, which says that the volume of the given gas at constant pressure is directly proportional to the temperature measured in Kelvin. As the volume increases, the temperature also increases, if the volume decreases, then the temperature also decreases.
As per the Charles law, here the volume is decreased from 50 ml to 25 ml so the boiling point also decreases.
Answer:
ΔH = - 5315 kJ.
Explanation:
The given chemical reaction is as follows -
2C₄H₁₀ (g) + 13 O₂ (g) → 8 CO₂ (g) + 10 H₂O (g) + 5315 kJ
In the above equation , the amount of energy i.e. 5315 kJ is released , i.e. it is in the product side , hence , the reaction is an example of an exothermic reaction .
Hence ,
The value of the change in enthalphy , i.e. , the enthalpy of product minus the enthalpy of the product .
Therefore ,
The value of the change in enthalphy = - ve .
Hence ,
ΔH = - 5315 kJ.
Answer:
The mass of nickel is 48μg
Explanation:
Parts per billion is a way to describe small concentrations and is defined as the ratio between μg of solute and kg of solvent.
If a solution of nickel in propanol is 20ppb, contains 20μg of nickel in 1 kg of propanol.
Thus, a sample of 2.4kg of propanol will contain:
2.4kg × (20μg nickel / 1kg) = 48μg nickel
<h3>The mass of nickel is 48μg</h3>
Answer:
No. Au⁺ has a complete 5d sublevel.
Explanation:
The color of the transition metal/ion arises due to d-d transition which means that when energy of certain frequency is passed though the solution of the transition metal ions, the electrons of the d orbital gain some energy and goes to higher energy level. The energy absorbed lies in the visible region and thus they are appeared colored.
The electronic configuration of Au is:
1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰6s¹
If the gold atom looses one electron, then the electronic configuration is:
1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰
<u>Hence, in the configuration, the 5d orbital is full filled and there is no scope for d-d transition. </u>
<u>Thus, there will Au⁺ will not be colored.</u>
Answer:
- <u><em>The bag with no sunscreen held the most vibrant beads.</em></u>
Explanation:
<em>SPF</em> is the Sun Protection Factor. It indicates how long a person can stay out in the sun before his skin start burning. It is a factor that is multiplied by 15 minutes. SPF 30 means 30 times 15 = 450 minutes. SPF 70 means 70 times 15 = 1,050 minutes.
Thus, the bag covered in <em>SPF 30</em> <em>sunscreen</em> will raise its temperature faster than the bag covered in <em>SPF 70 </em>sunscreen. And the bag with <em>no sunscreen </em>will raise its temperature faster than the other two.
The higher the temperature the more vibrant the particles that consititute the substances, thus, you conclude that the bag that held the most vibrant beads is the bag with no sunscreen.
Remember that the temperature is a measure of the kinetic energy:. The relation is: the higher the temperature the higher the kinetic energy.
Therefore, the more the particles vibrate, the higher the kinetic energy and the higher the temperature.