Answer:
these micronutrients are not produced in our bodies and must be derived from the food we eat.
Explanation:
Vitamins and minerals are micronutrients required by the body to carry out a range of normal functions. However, these micronutrients are not produced in our bodies and must be derived from the food we eat. Vitamins are organic substances that are generally classified as either fat soluble or water soluble.
 
        
             
        
        
        
Answer:
The mass of 10 cm³of a 0.4 g/dm³ solution of sodium carbonate is 0.004 grams
Explanation:
The question is with regards to density calculations
The density of the given sodium carbonate solution, ρ = 0.4 g/dm³
The volume of the given solution of sodium carbonate, V = 10 cm³ = 0.01 dm³


Therefore, we have;

The mass, "m", of the sodium carbonate in  = ρ×V = 0.4 g/dm³ × 0.01 dm³ = 0.004 g
The mass of 10 cm³ (10 cm³ = 0.01 dm³) of a 0.4 g/dm³ solution of sodium carbonate, m = 0.004 g.
 
        
             
        
        
        
Answer:
6.82g
0.59moles 
Explanation:
1. What is the mass sample of 0.0500 moles of zinc chloride ?
Given parameters: 
Number of moles ZnCl₂ = 0.05moles 
Unknown: 
Mass of the sample  =  ? 
Solution: 
To find the mass of a substance using the number of moles, it would be pertinent to understand what mole is. 
A mole is a substance that contains the avogadro's number of particles. 
It relates to the mass using the expression below; 
                 Mass of a substance  = number of moles x molar mass
Molar mass of  ZnCl₂; 
         Atomic mass of Zn  = 65.4g/mol
                                    Cl = 35.5g/mol
Molar mass = 65.4 + 2(35.5)  = 136.4g/mole 
Mass of a substance  = 0.05 x 136.4  = 6.82g
2. How many moles of potassium sulfide are in a 65.50g sample?
Given parameters: 
Mass of K₂S  = 65.5g
Unknown: 
Number of moles  = ? 
Solution: 
The number of moles of any substance is related to mass using the expression below; 
               Number of moles  = 
Molar mass of K₂S  = 2(39) + 32  = 110g/mol
               Number of moles  =  = 0.59moles
   = 0.59moles 
 
        
             
        
        
        
Answer:
That would be hydrogen and helium! :)
 
        
                    
             
        
        
        
Answer:
It slows down the transfer of thermal energy from outside to inside the coat.
Explanation: