The correct answer is option (B) lemon juice. 
pH refers to the logarithmic scale used to indicate the acidity or basicity of an aqueous solution. It is the negative of the base 10 logarithm of the activity of the hydrogen ion. Solutions with a pH less that 7 are considered acidic and the solutions with a pH greater that 7 are considered to be basic. A pH of 7 is neither an acid nor a base and is considered neutral. 
An acid has a high concentration of hydrogen ions (H+)  and a base has a low concentration of hydrogen ions. Higher the hydrogen ion concentration, pH is acidic. Among the given substances, lemon juice has a pH of 2, urine has a pH of 6, tomato juice has a pH of 4 and black coffee has a pH of 5.  Since lemon juice has a pH of 2, it has the lowest –OH ion concentration. 
 
        
                    
             
        
        
        
Answer:
B..........................
Explanation:
 
        
             
        
        
        
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The process that is similar to binary fission is Mitosis
        
                    
             
        
        
        
Answer:
 transport of protons (H+) from low concentration in the mitochondrial matrix to high concentration in the mitochondrial intermembrane space
Explanation:
atpase pump can also be called atp synthase. this enzyme catalyses atp formation from adenosine diphosphate and phosphate. it has f1, stalk and f0 components. 3 positive hydrogen ions go through to make 1 adenosine triphosphate molecule. oxidative phosphorylation has to do with the loss of electrons. there would be electrons loss from NADH to FADH2. Cytochromes carries them through different series of transferases from I to IV and while on this positive hydrogen ions are released into mitochondrial matrix
positive hydrogen ions are moved back to lumen through adenosine triphosphate channels. a process called chemiosmosis. the pro