In the physical properties, it is mentioned that the element has 4 valence electrons. The elements in the periodic table are arranged such that, the number of valence electrons present in the neutral atoms belonging to a particular group is equal to the group number.
Thus, the unidentified element can be best classified as a nonmetal in period 4
Ans C)
In chemistry the law of multiple proportions states that if two elements from more than one compound between them then the ratios of the masses of the second element which combine with a fixed mass of the first element will always be ratios of small whole numbers .
Complete Question
The complete question is shown on the first uploaded image
Answer:
The concentration of high-pressure side is 
Explanation:
From the question we are told that
The thickness of the polyethylene is 
The temperature is 
The flux is 
The concentration on the low-pressure side is 
The initial diffusivity is 
The activation energy for diffusion is 
Generally the diffusivity of the oxygen at 600 K can be mathematically evaluated as
substituting values
Generally the flux is mathematically represented as

Where
is the concentration of oxygen at the higher side
So

substituting values


Photosynthesis converts solar energy into chemical energy title