Answer:
volume is equal to the mass divided by the density (V = M/d).
The correct answer is - B) 650.
The Red Sea is a sea that grows in size because it is widening all the time. The rate of the widening is 1.25 centimeters per year, so it is not something that can be easily seen during a normal human lifespan, but over a longer period of time it will have a much different shape, size, and influence in the region. It is located between the African and the Arabian tectonic plates as an elongated thin sea with a northwest-southeast direction.
The widening of the Red Sea is due to the movement of the tectonic plates. Africa is moving towards northwest, and that makes it slowly distance itself from the Arabian plate, thus opening more space for the Red Sea.
In order for the Red Sea to widen another 812.5 centimeters, will be required 650 years, and we can come to the result by simple dividing the required number of the width with the annual widening.
812.5 / 1.25 = 650.
This problem is honestly, very easy. Just grab a periodic table and find the element in Group 1 and Period 7. But first, let's discuss how the elements are arranged systematically in a periodic table. There are a lot of scientists who contributed to it, but the most famous one is Dimitri Mendeleev. He arranged the elements according to their atomic number. The elements starts from 1 which is Hydrogen up to the heaviest known elements which is Oganesson with an atomic number of 118. As you can observe, there is a gap between groups 3 and 4. This is done so that the periodic table does not take too much space horizontally. Thus, they are just placed at the bottom. These elements are called lanthanides (upper row) and actinides (lower row). The rows in the periodic table are called groups, and the columns are called periods.
Now, the element at the lower left corner (Group 1, Period 7) is Francium, abbreviated as Fr. It has an atomic number of 87. Some elements are actually synthesized, but Francium is a naturally occurring radioactive element. It was discovered by Marguerite Perey in France.
The pressure of the oxygen gas collected : 718 mmHg
<h3>Further explanation</h3>
Given
P tot = 748 mmHg
P water vapour = 30 mmHg
Required
P Oxygen
Solution
Dalton's law of partial pressures states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the component gases
Can be formulated:
P tot = P1 + P2 + P3 ....
The partial pressure is the pressure of each gas in a mixture
P tot = P H₂O + P Oxygen
P Oxygen = 748 mmHg - 30 mmHg
P Oxygen = 718 mmHg