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The element "X" is "O" (oxygen).
<h3>Calculation:</h3>
Given,
Chemical formula = Na₂CX₃
Formula mass = 106 amu
Molar mass of Na = 23 amu
Molar mass of C = 12 amu
To find,
Element X =?
We will equate the equation as follows,
2(23) + 12 + 3(y) = 106
46 + 12 + 3y =106
58 + 3y = 106
3y = 106 - 58
3y = 48
y = 48/3
y = 16
We know that Oxygen has molecular mass of 16. Therefore the element "X" is "O".
Learn more about molar mass here:
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The gold leaf (not foil) is to give a sculpture or a painting appeal. Without it, it would discolour quicker.The gold leaf can be easily removed if needed to be.
Answer:

Explanation:
First of all we need to calculate the heat that the water in the cooler is able to release:

Where:
- Cp is the mass heat capacity of water
- V is the volume
is the density


To calculate the mass of CO2 that sublimes:

Knowing that the enthalpy of sublimation for the CO2 is: 


Bacterial cells can pick up the DNA through the process of transformation. Lambda phages are used by eliminating the middle of its liner genome and adding the foreign DNA in the created space. The phage is then introduced into the bacterial cell where it replicated itself via the lysogenic cycle.