A scientific model is a simplified version of some phenomenon that takes place in natural systems. A scientific model can be visual (flow charts), graphical, conceptual, or mathematical. These models are used to make predictions about how a set of conditions would change the present scenario in future. Scientific models can explain how the ongoing changes in the environment can show long term affect on our planet like the climate change. Therefore, a scientific model can be used to explain the phenomena like the effect of global air temperatures on the mean sea level around the world.

6 0

4 years ago

Which transition in the hydrogen atom produces emitted light with the longest wavelength?

monitta

Answer:

Red light has the longest wavelength

Explanation:

Red light is emitted when a high energy state electron drops from high energy level 3 to low energy level 2. Red light has the longest wavelength and lowest energy. It is a know fact that the shorter the drop within energy levels, the lesser the energy.

6 0

4 years ago

Is mass conserved when you burn wood?

Alex_Xolod [135]

No it is not conserved

7 0

4 years ago

A gas used to extinguish fires is composed of 75 % CO2 and 25 % N2. It is stored in a 5 m3 tank at 300 kPa and 25 °C. What is th

tatyana61 [14]

Answer : The partial pressure of the $CO_2$ in the tank in psia is, 32.6 psia.

Explanation :

As we are given 75 % $CO_2$ and 25 % $N_2$ in terms of volume.

First we have to calculate the moles of $CO_2$ and $N_2$ .

$\text{Moles of }CO_2=\frac{\text{Volume of }CO_2}{\text{Volume at STP}}=\frac{75}{22.4}=3.35mole$

$\text{Moles of }N_2=\frac{\text{Volume of }N_2}{\text{Volume at STP}}=\frac{25}{22.4}=1.12mole$

Now we have to calculate the mole fraction of $CO_2$ .

$\text{Mole fraction of }CO_2=\frac{\text{Moles of }CO_2}{\text{Moles of }CO_2+\text{Moles of }N_2}$

$\text{Mole fraction of }CO_2=\frac{3.35}{3.35+1.12}=0.75$

Now we have to calculate the partial pressure of the $CO_2$ gas.

$\text{Partial pressure of }CO_2=\text{Mole fraction of }CO_2\times \text{Total pressure of gas}$

$\text{Partial pressure of }CO_2=0.75mole\times 300Kpa=225Kpa=225Kpa\times \frac{0.145\text{ psia}}{1Kpa}=32.625\text{ psia}$

conversion used : (1 Kpa = 0.145 psia)

Therefore, the partial pressure of the $CO_2$ in the tank in psia is, 32.6 psia.

3 0

3 years ago