Missing question: Express the salt concentration in kg/m³.
Answer is: the salt concentration is 9.8 kg/m³.
m(NaCl) = 9.8 g ÷ 1000 g/kg.
m(NaCl) = 0.0098 kg.
V(solution) = 1 L = 1 dm³.
V(solution) = 1 dm³ ÷ 1000 dm³/m³.
V(solution) = 0.001 m³.
d(solution) = m(NaCl) ÷ V(solution).
d(solution) = 0.0098 kg ÷ 0.001 m³.
d(solution) = 9.8 kg/m³.
        
             
        
        
        
It went under a physical change because it (1) changed color. (2) changed form.
        
             
        
        
        
Answer:
2Fe + 3Cl2 → 2FeCl3
Explanation:
 Fe + Cl2 —> FeCl3
There are 3atoms of Cl on the right side and 2 atoms on the left side. Therefore, to balance Cl put 2 in front of FeCl3 and put 3 in front of Cl2 as shown below: 
Fe + 3Cl2 → 2FeCl3
Now, we see clearly that there are 2 atoms of Fe on the right side and 1 on the left side. This can be balanced by putting 2 in front of Fe as shown below:
2Fe + 3Cl2 → 2FeCl3
Now the equation is balanced. 
 
        
                    
             
        
        
        
Scientists prevent the nonpolar perfluorocarbons
in Oxygent from separating from the water by adding surfactant. 
<u>Explanation:</u>
The  collection of oxygen from lungs and transporting it  all those tissues present in the human body and taking carbon dioxide back to lungs are the main functions of the hemoglobin. But, instead of this hemoglobin, When perfluorocarbons
, a nonpolar chemical is used to perform the same function for the oxygen transportation, the nonpolar chemical may not mix well with the water when this perfluorocarbons is taken through a water-based saline
. 
For this purpose an addition of a chemical called surfactant is done. This will enhance the chemical bonding between the non polar chemical and water. The perfluorocarbons  spreads into some droplets and gets coated with this bonding substance. Thus it gets attached to the water.
 
        
             
        
        
        
Answer:
it's the third one
Explanation:
in the first one oxygen molecules aren't balanced
the second ok me oxygen isnt balanced
and the fourth one hydrogen isn't balanced
hope it helps ;)