Answer:

Explanation:
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In this case, since we can see that the heat released by the combustion of the mayonnaise is absorbed by the bomb calorimeter and water, we can set up the following equation:

Whereas q for mayonnaise stands for the heat due to its usage; thus, we plug in to obtain:

Now, if 10.0 g are eaten, the energy provided by it turns out:

And we need that value in dietary calories, 1 kcal:

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Answer :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule. The electrons are represented by dot.
The given molecule is, perbromate ion.
Bromine has '7' valence electrons and oxygen has '6' valence electron.
Therefore, the total number of valence electrons in perbromate ion,
= 7 + 4(6) + 1 = 32
According to Lewis-dot structure, there are 14 number of bonding electrons and 18 number of non-bonding electrons.
Formula for formal charge :

The Lewis-dot structure of perbromate ion is shown below.
The mass of a nickel coin is 5 g.
1 mol of Ni weighs 58 g. 1 mol contains 6.022 x 10²³ atoms of Ni.
therefore in 58 g there are 6.022 x 10²³ atoms of Ni
then in 5 g the number of Ni atoms are - 6.022 x 10²³ /58 x 5 = 5.2 x 10²² Ni atoms
Therefore number of Ni atoms are 5.2 x 10²² atoms in a nickel coin