#19 due to weathering and erosion the rock from the stream was smoothened and without as much the rock from deep underground was/is very rugged and natural.
#18 Due to wind patterns the sand dunes are blew around and the sands shift and fly around with nothing to keep the sand in place the sand can go long distances or come long distances.
You can determine this by counting the number of electrons on the last orbital. If the number of electrons on the last orbital (valence electrons) is 8 then it satisfies the octet rule because the compound has mirrored the look of a noble gass or “neutral” charge.
<u>Answer:</u> The volume of acid should be less than 100 mL for a solution to have acidic pH
<u>Explanation:</u>
To calculate the volume of acid needed to neutralize, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is HCl
are the n-factor, molarity and volume of base which is NaOH
We are given:

Putting values in above equation, we get:

For a solution to be acidic in nature, the pH should be less than the volume of acid needed to neutralize.
Hence, the volume of acid should be less than 100 mL for a solution to have acidic pH
Answer:
2Mg(s) + O2 (g) -> 2MgO(g)