Answer:
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5 is manganese (25Mn).
Explanation:
Step 1: Data given
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5
has 25 electrons.
This element has 2 electrons on the first shell, 8 electrons on the second shell, 13 electrons on the third shell and 2 electrons on the outer shell (valence electrons).
This means this element is part of group VII.
The element with 25 electrons, we can find on the periodic table, with atomic number 25.
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5 is manganese (25Mn).
Complete Question
A student is extracting caffeine from water with dichloromethane. The K value is 4.6. If the student starts with a total of 40 mg of caffeine in 2 mL of water and extracts once with 6 mL of dichloromethane
The experiment above is repeated, but instead of extracting once with 6 mL the extraction is done three times with 2 mL of dichloromethane each time. How much caffeine will be in each dichloromethane extract?
Answer:
The mass of caffeine extracted is 
Explanation:
From the question above we are told that
The K value is 
The mass of the caffeine is 
The volume of water is 
The volume of caffeine is 
The number of times the extraction was done is n = 3
Generally the mass of caffeine that will be extracted is
![P = m * [\frac{V}{K * v_c + V} ]^3](https://tex.z-dn.net/?f=P%20%3D%20%20m%20%20%2A%20%20%5B%5Cfrac%7BV%7D%7BK%20%2A%20%20v_c%20%2B%20V%7D%20%5D%5E3)
substituting values
![P = 40 * [\frac{2}{4.6 * 2 + 2} ]^3](https://tex.z-dn.net/?f=P%20%3D%20%2040%20%20%20%2A%20%20%5B%5Cfrac%7B2%7D%7B4.6%20%2A%20%202%20%2B%202%7D%20%5D%5E3)
To solve this we assume
that the gas is an ideal gas. Then, we can use the ideal gas equation which is
expressed as PV = nRT. At a constant temperature and number of moles of the gas
the product of PV is equal to some constant. At another set of condition of
temperature, the constant is still the same. Calculations are as follows:
P1V1 =P2V2
P2 = P1V1/V2
P2 = 740mmhg x 19 mL / 30 mL
<span>P2 = 468.67 mmHg = 0.62 atm</span>
Answer:
1. First one is true : as per periodic table down the group , the elements has increasing order of shell & with that the London dispersion forces brings the inter-molecules close together and bromine converted into liquid .
2. second one is False because carbon-carbon bonds are not weak bonds they form mutual covalent bonds which are stronger bonds and cannot be easily disrupted .
3. A single carbon atom has the valency of 4 so it can be bonded with four hydrogen atom at the same time .
Explanation:
