Answer: 28.1 amu
Explanation:
Mass of isotope 1 = 27.98 amu
% abundance of isotope 1 = 92.21% = 
Mass of isotope 2 = 28.98 amu
% abundance of isotope 2 = 4.70% = 
Mass of isotope 3 = 29.97 amu
% abundance of isotope 2 = 3.09% = 
Formula used for average atomic mass of an element :

![A=\sum[(27.98 )\times 0.922+(28.98)\times 0.047+(29.97)\times 0.0309]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%2827.98%20%29%5Ctimes%200.922%2B%2828.98%29%5Ctimes%200.047%2B%2829.97%29%5Ctimes%200.0309%5D)

Therefore, the average atomic mass of silicon is 28.1 amu
Answer: Soaps are sodium or potassium fatty acids salts, produced from the hydrolysis of fats in a chemical reaction called saponification. Each soap molecule has a long hydrocarbon chain, sometimes called its 'tail', with a carboxylate 'head'.
Explanation: Saponification is an exothermic chemical reaction—which means that it gives off heat—that occurs when fats or oils (fatty acids) come into contact with lye, a base. In this reaction, the triglyceride units of fats react with sodium hydroxide or potassium hydroxide and are converted to soap and glycerol.
Answer:
Yeast and mushroom
Explanation:
Yeast and mushroom appears in decaying substances.
It equals 0.005 but plz mark this as the brainliest question plz
Reaction equation:
Zn + 2HCl → ZnCl₂ + H₂
One mole of gas occupies 22.4 L at STP
Moles of H₂ = 112/22.4
= 5 moles
The theoretical amount of Zn needed is 5 mol
The actual amount = 5/0.85
= 5.88 moles
mass = moles x Mr
mass = 5.88 x 65
mass = 382.2 g
The answer is D.