Answer:  B- Chemical bonds are formed. Energy is released in the form of heat.
Explanation: I hoped that helped ! 
 
        
                    
             
        
        
        
Answer:
D is correct 
Explanation:
because 
we know that 
density of lead is 11.36 g/cm3
and 
density of tin is 7.31 g/cm3
so..
density of alloy by mixing 50/50
=(11.36+7.31)/2 g/cm3
=18.67/2 g/cm3
=9.33 g/cm3
 
        
             
        
        
        
When E° cell is an electrochemical cell which comprises of two half cells.
 
So,
when we have the balanced equation of this half cell :
Al3+(aq) + 3e- → Al(s)   and E°1 = -1.66 V 
and we have  also this balanced equation of this half cell :
Ag+(aq)  + e- → Ag(s)  and E°2 = 0.8 V 
so, we can get E° in Al(s) + 3Ag (aq) → Al3+(aq) + 3Ag(s)
when E° = E°2 - E°1
∴E° =0.8 - (-1.66)
      = 2.46 V
∴ the correct answer is 2.46 V
        
             
        
        
        
Input the atomic masses of Mg and P to give 134.84g/mol
Explanation:
The molar mass of a substance (atom or molecule or compound) is the mass in grams of one mole of the substance: 
 When dealing with an element the molar mass is the relative atomic mass expressed as g/mol. 
For compounds, you add the atomic masses of the component atoms and you sum up. 
You simply input the atomic mass of 3 atoms of Mg and 2 atoms of P
 Atomic mass of Mg = 24.3g/mol 
                              P = 30.97g/mole 
Molar mass of Mg₃P₂ = 3(24.3) + 2(30.97) = 134.84g/mol
learn more: 
Molar mass brainly.com/question/2861244
#learnwithbrainly
 
        
             
        
        
        
Answer:
Substance 4
Explanation:
Density is defined as mass per unit volume. A substance floats in another when its density is less than that of the substance on which it floats.
If an object is immersed in a denser liquid, it will sink
Since the density of water is 1 g/cm^3, any substance whose density is less than that of water will float in it.
If we look at the table, substance 4 has a density of 0.5g/cm^3. Hence, substance 4 is expected to float in water.