Answer: single replacement reaction, 
Explanation:
A single replacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution. 
A general single displacement reaction can be represented as :

As strontium metal is added to aluminum chlorate , strontium being more reactive than aluminium, displaces aluminium atom its salt solution and lead to formation of strontium  chlorate and aluminum metal.

 
        
             
        
        
        
Answer:
caused by the ability of electrons to flow from one half cell too the other
Explanation:
How is the potential voltage of a redox reaction?
The potential difference is caused by the ability of electrons to flow from one half cell to the other. Electrons are able to move between electrodes because the chemical reaction is a redox reaction. A redox reaction occurs when a certain substance is oxidized, while another is reduced.
 
        
             
        
        
        
Answer:
16.89g of PbBr2
Explanation:
First, let us calculate the number of mole of Pb(NO3)2. This is illustrated below:
Molarity of Pb(NO3)2 = 0.595M
Volume = 77mL = 77/1000 = 0.077L
Mole =?
Molarity = mole/Volume 
Mole = Molarity x Volume 
Mole of Pb(NO3)2 = 0.595x0.077
Mole of Pb(NO3)2 = 0.046mol 
Convert 0.046mol of Pb(NO3)2 to grams as shown below:
Molar Mass of Pb(NO3)2 =
207 + 2[ 14 + (16x3)] 
= 207 + 2[14 + 48] 
= 207 + 2[62] = 207 +124 = 331g/mol 
Mass of Pb(NO3)2 = number of mole x molar Mass = 0.046 x 331 = 15.23g
Molar Mass of PbBr2 = 207 + (2x80) = 207 + 160 = 367g/mol
Equation for the reaction is given below:
Pb(NO3)2 + CuBr2 —> PbBr2 + Cu(NO3)2
From the equation above, 
331g of Pb(NO3)2 precipitated 367g of PbBr2
Therefore, 15.23g of Pb(NO3)2 will precipitate = (15.23x367)/331 = 16.89g of PbBr2
 
        
             
        
        
        
A substance that undergoes change during a reaction, usually from coming in contact with another substance