A beaker of black powder can be a mixture with different substances (i.e gunpowder: a mixture of sulfur, charcoal, etc.), an element which can probably be carbon (known as black), and a compound as well which can be potassium nitrate. Hence, the answer is D. 
        
                    
             
        
        
        
You'll want to add three amounts of heat. 
(1) Specific heat of lowering the temperature from -135°C to the melting point -114°C
(2) Latent heat of fusion/melting
(3) Specific heat of elevating the temperature from -114°C to -50°C
(1) E = mCΔT = (25 g)(0.97 J/g·°C)(1 kJ/1000 J)(-114 - -135) = 0.509 kJ
(2) E = mΔH = (25 g)(5.02 kJ/mol)(1 mol/46.07 g ethanol) = 2.724 kJ
(3) E = mCΔT = (25 g)(2.3 J/g·°C)(1 kJ/1000 J)(-50 - -114) = 3.68 kJ
<em>Summing up all energies, the answer is 6.913 kJ.</em>
        
             
        
        
        
Answer:
16
Explanation:
The proton number is always the number in the corner of the box on a periodic table 
 
        
                    
             
        
        
        
Answer:
80.07 g/mol
Explanation:
Sulfur's g/mol = 32.07
Oxygen's g/mol = 16.00
32.07 + 16.00(3) = 80.07 g/mol
 
        
                    
             
        
        
        
An atom's mass is determined by its protons and neutrons. 
An atom's charge is determined by its number of protons minus it number of electrons.
Atoms become cations, or positively charged when they lose an electron, and since electrons have a negative charge, they become anions, or negatively charged.
Water is a universal solvent.
Carbohydrates (carbs) are used by the body for energy.
Steroids and triglycerides are lipids.
Proteins that catalyze chemical reactions are called enzymes.