Explanation:
In a covalent bond, there is sharing of the donated electron by two atomic species having very small electronegative differences between them. 
Oxidation is the loss of electrons by a specie and it usually lead to an increase in oxidation number. 
 Reduction is the gain of electrons by a specie. It leads to a lower oxidation number. 
Since there is no actual loss of gain of electrons in a covalent body, the electronegativiy is at work. 
Electronegativity is the ability of a specie to draw the shared electrons more to itself in a covalent bond. 
- Between two atoms bonded covalently, the more electronegative specie draws the electrons closer. 
- This leaves a partial negative charge on it. 
- The other electron then becomes partially positively charged. 
- We can then say, the more electronegative specie undergoes reduction. 
- The less electronegative one undergoes oxidation. 
learn more:
Covalent bond brainly.com/question/3064597
Oxidation and reduction brainly.com/question/2278247
#learnwithBrainly
 
        
             
        
        
        
Only when you are in love with a person... Otherwise they seem normal to you
        
             
        
        
        
<u>Answer</u>:
Concave shape of the wave rock  is a physical evidence that  supports the evolution of earth due chemical weathering
<u>Explanation</u>: 
It is the best physical evidence of collection in the earth’s evolution. The earth surface is 2.7 billion years old, also the basis for formation of Australian continent formation. The wave rock is formed by weathering of the surrounding area, which helps in proving the deposition part, as the wave rock was below the ground, occurred due to deposition of rock years over years. It is made from very tough material from its surrounding. The weathering reduced the surrounding terrain, while the bedrock remained to witness for the history.  
 
        
                    
             
        
        
        
Answer: Sometimes. 
Explanation: Well, it depends on the other conditions, what is in the soil, etc.
 
        
                    
             
        
        
        
In order to test the presence of starch, one has to treat with iodine. If the food turns blue-black in color, it is an indication of the presence of the starch.