Scientists should control most possible variables in experiments to get the most valid and correct data. If many variables are included in experiments it is more difficult to interpret what is causing a different outcome.
Answer:
AB + CD ----> AC + BD
Explanation:
If you think this reaction:
AB + CD ----> AC + BD
(Reactants) (Products)
All the statements are true.
<span><em>Answer:</em>
A strontium-90 atom that has a lost two electrons has <u>38</u> protons, <u>52</u> neutrons, and <u>36</u> electrons.
<em>Explanation:
</em>Atomic number<em> of </em>Strontium (Sr) is 38.
<em>Atomic number = number of protons
</em>Hence, Strontium has 38 protons.
If the element is in neutral state,
number of protons = number of electrons.
Then, neutral Strontium atom should have 38 electrons.
But the question says Sr has lost 2 electrons. Hence, number of electrons should be 38 - 2 = 36.
Mass number = number of protons + number of neutrons.
The given mass number is 90. Hence, number of neutrons should be 90 - 38 = 52.</span>
Answer: The approximate equilibrium partial pressure of 
is 3.92 atm
Explanation:
Equilibrium constant is the ratio of the concentration of products to the concentration of reactants each term raised to its stochiometric coefficients.
The given balanced equilibrium reaction is,
![K_p=\frac{[H_2]^2\times [S_2]}{[H_2S]^2}](https://tex.z-dn.net/?f=K_p%3D%5Cfrac%7B%5BH_2%5D%5E2%5Ctimes%20%5BS_2%5D%7D%7B%5BH_2S%5D%5E2%7D)
![1.5\times 10^{-5}=\frac{[H_2]^2\times [S_2]}{[H_2S]^2}](https://tex.z-dn.net/?f=1.5%5Ctimes%2010%5E%7B-5%7D%3D%5Cfrac%7B%5BH_2%5D%5E2%5Ctimes%20%5BS_2%5D%7D%7B%5BH_2S%5D%5E2%7D)
On reversing the reaction:
initial pressure 4.00atm 2.00 atm 0
eqm (4.00-2x)atm (2.00-x) atm 2x atm
![K_p=\frac{[H_2S]^2}{[H_2]^2\times [S_2]}](https://tex.z-dn.net/?f=K_p%3D%5Cfrac%7B%5BH_2S%5D%5E2%7D%7B%5BH_2%5D%5E2%5Ctimes%20%5BS_2%5D%7D)
![0.67\times 10^5=\frac{2x]^2}{[4.00-2x]^2\times [2.00-x]}](https://tex.z-dn.net/?f=0.67%5Ctimes%2010%5E5%3D%5Cfrac%7B2x%5D%5E2%7D%7B%5B4.00-2x%5D%5E2%5Ctimes%20%5B2.00-x%5D%7D)
![[H_2S]=2x=2\times 1.96=3.92 atm](https://tex.z-dn.net/?f=%5BH_2S%5D%3D2x%3D2%5Ctimes%201.96%3D3.92%20atm)
Thus approximate equilibrium partial pressure of is 3.92 atm
