Answer:
The answer is given below in the picture
Explanation:please check it
The two reason behind the invalidity of flame test are false positive and false negative.
while performing the flame test you must have to be accurate otherwise you will get false results may be positive for some element or may be negative in case the element is present. The main reason to get the false positive and false negative is the presence and contamination of sodium.
Answer : The volume of the cube is, 
Solution : Given,
Density of nickel = 
Number of nickel atoms = 
Molar mass of nickel = 58.7 g/mole
First we have to calculate the moles of nickel.
As, 
atoms form 1 mole of nickel
So, atoms form 
moles of nickel
The moles of nickel = 3.321 moles
Now we have to calculate the mass of nickel.
The mass of nickel = 194.94 g
Now we have to calculate the volume of nickel.
Therefore, the volume of the cube is,
When sulfur reacts with zinc metal is forms a compound known as zinc sulfide.
<h3>
Name of the elements</h3>
The names of the elements that make up the compound will be determined from the atomic mass of the elements.
<h3>Which element has atomic number 30</h3>
The element that atomic number of 30 is zinc and it has oxidation number of +2.
<h3>Which element has atomic number 16</h3>
The element that atomic number of 16 is sulfur and it has oxidation number of -2.
<h3>Chemical reaction between sulfur and zinc metal</h3>
Zn²⁺ + S²⁻ --------> ZnS
Thus, when sulfur reacts with zinc metal is forms a compound known as zinc sulfide.
Learn more about zinc sulfide here: brainly.com/question/20806552
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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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