Answer:
2. 
3. 
Explanation:
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2. In this case, we can evidence the problem by which volume and temperature are involved, so the Charles' law is applied to:

Thus, considering the temperatures in kelvins and solving for the final volume, V2, we obtain:

Therefore, we plug in the given data to obtain:

3. In this case, it is possible to realize that the 3.7 moles of neon gas are at 273 K and 1 atm according to the STP conditions; in such a way, considering the ideal gas law (PV=nRT), we can solve for the volume as shown below:

Therefore, we plug in the data to obtain:

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Answer:
Explanation:
a )
m = m₀ 
m is mass after time t . original mass is m₀ , λ is disintegration constant
λ = .693 / half life
= .693 / 1590
= .0004358
m = m₀ 
b )
m = 50 x 
= 40.21 mg .
c )
40 = 50 
.8 = 
= 1.25
.0004358 t = .22314
t = 512 years .
The data on Climate change is as explained below-
Explanation:
Climate change is the ominous “hard truth” concurrently. However, it is not the first time that climate change is happening. In geological history, we find plenty of evidence of climate change.
The most important and famous of all such changes is the climate change that occurred during the Mesozoic era leading to the extinction of Dinosaurus. The reason behind these all climate changes was different. However, the climate change we are witnessing at present has something extra to all this natural stuff.
The present climate change is fuelled by anthropogenic activities at large. Large scale emission of greenhouse gases possibly from burning of fossil fuels ever since the Industrial revolutions in the late 18th century has altered the chemical composition of atmospheric gases. In addition to the use of fossil fuels other activities such as agriculture, coal-based power plants, deforestation and other such activities have been instrumental in degrading the serene balance between different atmospheric gases.
The evidence of the present climate change can be gauged in-
- The rise in global average temperature-Earth’s mean temperature has risen by around 1° C ever since the 19th century. 2017 proved to be the warmest year in the record.
- Oceans have been net absorber of the heat. This has led to the warming up of oceans. This severely hampers and impact marine flora and fauna
- Deglaciation- the increasing temperature has manifested in the form of shrinking ice-sheets. Large icebergs are calving and thus has some serious long-term impact for the sustenance of mankind.
- Rise in the mean sea level- The sea level has risen by almost 10 inches since last century. This increase is all set to increase in future thus endangering the lives and livelihood of the coastal communities.
All the leading personalities of the time including the ex-president of the US Mr Barak Obama emphasised the importance of climate change and urged the global community to tackle it at earliest. In his words, he mentioned, “No other challenge poses as great a threat to the future generation as the climate change”. In addition to Mr Obama, noted climate activist Greta Thunberg described the climate change to be the greatest crisis to the humanity that it has ever faced.
Therefore, it can be safely argued that it’s urgent to talk and act tough on climate change. Climate change has transitioned into a multi-headed monster capable enough to devastate the entire mankind. It has done this earlier and sure to carry it further on.
Limiting reactant : O₂
Mass of N₂O₄ produced = 95.83 g
<h3>Further explanation</h3>
Given
50g nitrous oxide
50g oxygen
Reaction
2N20 + 302 - 2N204
Required
Limiting reactant
mass of N204 produced
Solution
mol N₂O :

mol O₂ :

2N₂O+3O₂⇒ 2N₂O₄
ICE method
1.136 1.5625
1.0416 1.5625 1.0416
0.0944 0 1.0416
Limiting reactant : Oxygen-O₂
Mass N₂O₄(MW=92 g/mol) :

Answer: Light, Thermal, Kinetic
Explanation:
The lamp converts the electric energy to light energy.
The toaster converts the electric energy to thermal energy.
The fan converts the electric energy to kinetic energy.
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