No, this item is not made of pure silver because if it has been made from pure silver that it would have displaced only 1.16cm³ of water but due to the addition of some other low-density element it displaces 1.9cm³ of water.
<u>For pure silver</u>
density of pure silver is = 10.49 g/cm³
mass of silver = 12.2 gram
since, density = mass/volume
volume = mass/density
= 12.2/10.49 cm³
= 1.16 cm³
But the actual displaced water is <u>1.9cm³</u>, which means some other element of lower density has been added.
Therefore, it is clear that the given jewelry is not made of pure silver.
Learn more about silver here:-brainly.com/question/17086277
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In order to clasify these based on the type of polymer they are made from, we can say that B. <span>Leather shoes are made from natural polymers; raincoats are made from synthetic polymers, is the most accurate option from the ones you are giving me. Hope this is useful</span>
Using the law of <span>dilution:
</span>initial Molarity = 3.5x10⁻⁶ M
<span>Initial volume = 4.00 mL
</span>
final Molarity = ??
final volume = 1.00 mL
Therefore:
Mi x Vi = Mf x Vf
(3.5x10⁻⁶) x 4.00 = Mf x 1.00
1.4x10⁻⁵ = Mf x 1.00
Mf = 1.4x10⁻⁵ / 1.00 =
1.4x10⁻⁵ M
Answer : The heat of reaction for the process is, 1374.7 kJ
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The main chemical reaction is,

The intermediate balanced chemical reaction will be,
(1)

(2)

(3)

We reversing reaction 1, 3 and multiplying reaction 2 by 2 and then adding all the equations, we get :
(1)

(2)

(3)

The expression for heat of reaction for the process is:



Therefore, the heat of reaction for the process is, 1374.7 kJ