Answer:
9.96*10^21
Explanation:
Molar mass of K2O=29*2+16
= 74g per mol
number of moles in the sample= 1.224/ 74
=0.1654
Number of particles in 1 mole=6.0221409*10^23
Number of particles= 0.01654*6.0221409*10^23
=9.96*10^21
Answer:
Na ·
Explanation:
Hello!
In this case, since the Lewis dot structure of any element illustrates the number of valence electrons at the outer shell; we can set up the electron configuration of sodium to obtain:

We can see there is only one valence electron, for that reason the Lewis dot structure is:
Na ·
Whereas the dot represents the valence electron.
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The density is one gram per mL, so 1.
This is an example of displacement reaction
<u>Explanation:</u>
- The chemical reaction in which the one element replaces the other element in a compound is called a displacement reaction. This reaction is also called a replacement reaction.
AB + C -----> AC +B
2ZnS + 3O2 -----> 2ZnO + 2SO2
- This happens when A is more reactive than B and gives a stable product. Here the zinc sulfide compound reacts with the oxygen element to the stable product of zinc oxide and sulfur dioxide.
- In short, the more reactive element displaces the less reactive element is called a displacement reaction.