First, we have to get how many grams of C & H & O in the compound:
- the mass of C on CO2 = mass of CO2*molar mass of C /molar mass of CO2
                                        = 0.5213 * 12 / 44 = 0.142 g
- the mass of H atom on H2O = mass of H2O*molar mass of H / molar mass of H2O
                                                 =0.2835 * 2 / 18 = 0.0315 g
- the mass of O = the total mass - the mass of C atom - the mass of H atom
                          =  0.3 - 0.142 - 0.0315 = 0.1265 g
Convert the mass to mole by divided by molar mass
C(0.142/12) H(0.0315/2) O(0.1265/16) 
C(0.0118) H(0.01575) O(0.0079) by dividing by the smallest value 0.0079
C1.504 H3.99 O1 by rounding to the nearst fraction
C3/2 H4/1 )1/1 multiply by 2 
∴ the emprical formula C3H8O2
           
        
             
        
        
        
Answer: Final temperature = 206∘C
Explanation:
 Heat Energy is given as   
 q= mCΔT 
 ehere 
q= Heat energy = 87.4J
m= mass=1.25g
C=specific heat c= 0.386Jg∘C) , 
 ΔT =  Change in temperate of which the final temperature= 25.0∘C
  q= mCΔT 
 ΔT = q/mC
ΔT = 87.4/ 1.25 X 0.386=181.14∘C
But, 
 T final- T initial = ΔT
T final = T initial + ΔT
 T final = 25.0∘C +181.14∘C=206.14∘C rounded to 206∘C
 
        
             
        
        
        
1.) 28.0 grams of oxygen
28 grams (1 mole/16 grams per mole)=1.75 moles oxygen
2.)5.0 moles of Iron
5 moles(55.845 grams/1 mole)=279.225 grams Iron
3.) 452 grams Argon
452 grams(1 mole/39.948 grams)=11.315 moles Argon
4.) 16.5 moles Hydrogen
16.5 moles(1.01 grams/1 mole)=16.665 grams Hydrogen
        
             
        
        
        
The 'dark side' of the Moon refers to the hemisphere of the Moon that is facing away from the Earth. ... It is only 'dark' to us, as that hemisphere can never be viewed from Earth due to a phenomenon known as 'Tidal Locking'