Answer:
There are many different types of preservatives like Benzoic acid, Calcium Sorbate, Erythorbic Acid, Potassium Nitrate and Sodium Benzoate. Some act like antioxidants used for slowing down spoilage like Ascorbyl Palmitate, Butylated Hydroxy anisole (BHA) and Butylated Hydroxytoluene (BHT
 
        
             
        
        
        
. The energy of shells in a hydrogen atom is calculated by the formula E = -Eo/n^2 where n is any integer, and Eo = 2.179X10^-18 J. So, the energy of a ground state electron in hydrogen is: 
E = -2.179X10^-18 J / 1^2 = -2.179X10^-21 kJ 
Consequently, to ionize this electron would require the input of 2.179X10^-21 kJ 
2. The wavelength of a photon with this energy would be: 
Energy = hc/wavelength 
wavelength = hc/energy 
wavelength = 6.626X10^-34 Js (2.998X10^8 m/s) / 2.179X10^-18 J = 9.116X10^-8 m 
Converting to nanometers gives: 91.16 nm 
3. Repeat the calculation in 1, but using n=5. 
4. Repeat the calculation in 2 using the energy calculated in 3.
 
        
                    
             
        
        
        
Heat Transfer Lab
The following represents a lab set up for heat transfer. The cup on the left started with boiling water at 100 degrees C and the cup on the right has water at 20 degrees C. There is an aluminum bar between the two cups allowing heat to transfer from one cup into the other. The set up will be left alone for 20 minutes and temperatures of each cup of water will be recorded every minute for 20 minutes.
mag-aral ka
 
        
             
        
        
        
Answer: An existing theory is modified so that it can explain both the old and new observations. 
Explanation: