Hey!
I would say the answer is A. Plow the soil many times to lessen the chance of the topsoil being blown away.
Hope this helps !
Answer:
D
. A substance with a pH of 8
Explanation:
pH stands for <em>"Potential for Hydrogen." </em>This is an indicator of a solution's acidity or alkalinity. It is also used to tell <em>which chemicals are great for cleaning. </em>
pH 7 and pH 8 are both considered<em> "neutral pH,"</em> thus, solutions with these pH are often used as<em> dishwashing detergents </em>because they do not destroy the surfaces of objects. However, pH 8 is said to be<u> more alkaline in nature</u>. This allows it to destroy the residues, such as <em>fats and oils</em>, in pots and pans. It is the<em> pH of baking soda.</em>
Heat will go from hot coffee to the cold cream and vise versa
The Half life is the time taken for a radioisotope or a radioactive substance to decay by half its original amount. The half life of carbon 14 is 5600 years.
Original mass is 100%
Remaining amount is 24%
Therefore; 0.24 = 1 × (1/2)^n
n = log 0.24/log 0.5
= 2.06
therefore, the age of the fossil is 5600×2.06
= 11529.8
≈ 11529 years
Answer : The entropy change for the surroundings of the reaction is, -198.3 J/K
Explanation :
We have to calculate the entropy change of reaction 
.
![\Delta S^o=[n_{NH_3}\times \Delta S^0_{(NH_3)}]-[n_{N_2}\times \Delta S^0_{(N_2)}+n_{H_2}\times \Delta S^0_{(H_2)}]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo%3D%5Bn_%7BNH_3%7D%5Ctimes%20%5CDelta%20S%5E0_%7B%28NH_3%29%7D%5D-%5Bn_%7BN_2%7D%5Ctimes%20%5CDelta%20S%5E0_%7B%28N_2%29%7D%2Bn_%7BH_2%7D%5Ctimes%20%5CDelta%20S%5E0_%7B%28H_2%29%7D%5D)
where,
= entropy of reaction = ?
n = number of moles
= standard entropy of 
= standard entropy of 
= standard entropy of 
Now put all the given values in this expression, we get:
![\Delta S^o=[2mole\times (192.5J/K.mole)]-[1mole\times (191.5J/K.mole)+3mole\times (130.6J/K.mole)]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo%3D%5B2mole%5Ctimes%20%28192.5J%2FK.mole%29%5D-%5B1mole%5Ctimes%20%28191.5J%2FK.mole%29%2B3mole%5Ctimes%20%28130.6J%2FK.mole%29%5D)
Therefore, the entropy change for the surroundings of the reaction is, -198.3 J/K
