Answer: Option (a) is the correct answer.
Explanation:
A protein part of an enzyme is known as an apoenzyme. An apoenzyme combines with a cofactor, it is known as holoenzyme. 
Without a cofactor an apoenzyme cannot function as cofactor helps in the formation of an active enzyme system and provides a specific site on enzyme for the substrate. 
Whereas a non-protein chemical compound or metal ion that helps in the activity of enzyme as a catalyst is known as a cofactor. A metal ion cofactor can be bound directly to the enzyme or to a coenzyme.
The organic non-protein molecules which bind to the protein molecule to form an active enzyme is known as a coenzyme. Coenzymes are small size molecules which help the enzymes to act as a catalyst.
Therefore, we can conclude that the statement an apoenzyme can catalyze its reaction without its cofactor, is false.
 
        
             
        
        
        
Answer:
This experiment is uncontrolled because two different masses of substance A are used.
Explanation:
A controlled experiment is a structured experiment aimed at testing a particular observation or observations. The setup of a controlled experiment helps to determine the reason why a particular observation occurs and what must have led to it. 
In the experiment highlighted above, different masses of a substance were used, they were heated to different temperatures. The set up does not show any correlation between the masses of substances heated and the temperatures. It is even difficult to try to predict the hypothesis for this kind of experimental set up. All the variables in play can best be assumed to be independent of one another. 
 
        
                    
             
        
        
        
When you have both of these ( The periodic table of elements and the formula of your compound) you are able to calculate the R.M.M ( Relative atomic mass) of that compound.
For example the formula of a NaCl ( Table salt ) has the elemnt Na and Cl.
We look at the atomic mass of both of these compounds
Na - 23
Cl - 35.5
R.M.M = 23 +35.5 = 58.5
Hope this helps :).
        
             
        
        
        
I think the answer is ( A and C ) why I picked a and c it’s because a and c look the same answer. I hope it helped you
        
             
        
        
        
Answer:
OH⁻
Explanation:
A base is defined as a substance which interacts with water to yield excess hydroxide ions, OH⁻, in an aqeous solution.
Examples are Sodium hydroxide (NaOH) 
 Potassium hydroxide (KOH)
Bases are generally certain metallic oxides, metallic hydroxides and aqueous ammonia.
An acid is a proton donor, H⁺ and it interacts with water to produce excess hydroxonium ions in an aqueous solution.