The one on the left is pure because it is made out of one single material. The one on the right is a mixture because it is made out of multiple materials
        
                    
             
        
        
        
Answer:
Option : KBr + I -> KBr+I
Explanation:
Single-replacement reaction or single displacement reactions are a type of chemical reactions in which a whole compound reacts with an element in such a way that the element takes place of one of the compound's own elements and sets it free.
If we talk about KBr and I displacement reaction is not possible among these because Iodine is less reactive than Bromine that is why it will not react with KBr or replace Br.
                        KBr + I -> KBr+ I
Potassium Bromide + Iodine -> Potassium bromide + Iodine
Hope it help!
 
        
             
        
        
        
Carbon Dioxide is used in celular respiration. All other choices are waste products
        
             
        
        
        
Answer:
Explanation:
pH + pOH = 14 
pH + 10 = 14 
pH = 14 - 10 = 4 
Therefore pH of the solution is 4 . 
 
        
             
        
        
        
Answer:- Mass of the alloy is 2.8 kg. 
Solution:- Mass of Cr in the alloy is 325 g and mass of Fe in the alloy is 2.5 kg. Mass of alloy would be the sum of masses of constituent metals. 
Masses of the metals are not in the same units. So, we need to make the units equal. The want answer in kg so let's convert mass of Cr from g to kg.
Since, 1000 g = 1 kg
So, 
= 0.325 kg
Mass of alloy = mass of Cr + mass of Fe
mass of alloy = 0.325 kg + 2.5 kg = 2.825 kg
If we consider significant figures then as per the rules, the answer should not have more than one decimal place. 
So, 2.825 kg is round off to 2.8 kg and hence the mass of the alloy is 2.8 kg.