From the chemical formula the total mass of the compound can be determined. The mass of the 1 mole of the compound is its molar mass. The atom by which the molecule is generated, the mass of these atoms are expressed in terms of amu or atomic unit mass, but after formation of a molecule in a particular ratio the mass of each of the atom becomes the total molecular weight of the generated molecule. In this case the molecule posses three atoms X, Y and Z which are in a ratio of 2:2:7. Thus the chemical formula of the compound can be written as 
.
So the total mass of the compound in amu is {(2×47)+(2×42)+(7×16)} = {94+84+112}=290 amu.
Thus 1 mole of the compound contains 290 amu or 290 g by mass.
Henceforth 20 gram of the compound is equivalent to (20/290) = 0.068 mole.
Activation energy is the energy needed to begin breaking the bonds of reactants and is denoted as option D.
<h3>What is a Reactant?</h3>
These are the substances which take part in a chemical reaction and result in the formation of the product.
The activation energy is required as it breaks the bonds of the reactant thereby resulting in the product being formed. This therefore makes it the most appropriate choice.
Read more about Activation energy here brainly.com/question/5280701
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Answer:
1230
Explanation:
1.20×1025=1230 is your answer
Answer: B) Wood Shavings
Reason/Explanation:
Notice what options A, C, and D have on common. Ice, salt and sugar. Those are all dissolvable. Insoluble means un-able to dissolve. It can't dissolve. Wood shavings can't dissolve in water. They will just float. Sugar, salt and ice will all dissolve. Wood shavings won't.
-DustinBR
Answer: The pH will be 3.87
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)
According to stoichiometry,
1 mole of 
gives 1 mole of 
Thus 
moles of gives =
moles of
Putting in the values:
![pH=-\log[0.000134]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5B0.000134%5D)
Thus the pH will be 3.87
