Answer:What is the question
Explanation:
 
        
             
        
        
        
Molar mass Pb = 207.2 g/mol
1 mole Pb ------------- 207.2
? mole Pb ------------ 9.51 x 10³
moles = 9.51 x 10³ * 1 / 207.2
moles = 9.51 x 10³ / 207.2
= 45.89 moles
hope this helps!
        
             
        
        
        
According to Raoult's low:
We will use this formula: Vp(Solution) = mole fraction of solvent * Vp(solvent)
∴ mole fraction of solvent = Vp(Solu) / Vp (Solv)
when we have Vp(solu) = 25.7 torr & Vp(solv) = 31.8 torr 
So by substitution:
∴ mole fraction of solvent = 25.7 / 31.8 =0.808 
when we assume the moles of solute NaCl = X 
and according to the mole fraction of solvent formula:
mole fraction of solvent = moles of solvent / (moles of solvent + moles of solute)
by substitute:
∴ 0.808 = 0.115 / (0.115 + X)
 So X (the no.of moles of NaCl) = 0.027 m
        
             
        
        
        
Answer: I have no idea what kind of question this is, but I'm assuming it's a true or false question, and this is true. Although the north-bound pole is south-seeking, a compass would eventually draw you to the North Pole.
Explanation:
 
        
             
        
        
        
Hey there!:
absorbance = log 100 - log Transmitance
absorbace = 0.85
log 100 = 2
- log transmitance = absorbace / log 100
 0.85 / 2= 0.425
transmitance =  10 ^ ( - 0.425 )
transmitance = 0.376