Answer:

Explanation:
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In this case, according to the given chemical reaction, it possible for us to set up the expression for the calculation of the enthalpy change as shown below:

Thus, given the values of the enthalpies of formation on the attached file, we obtain:
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The reaction is not balanced
<h3>Further explanation</h3>
Given
Reaction
2Fe(s)+3O₂(g)⇒2Fe₂O₃(s)
Required
The number of atoms
Solution
In a balanced chemical equation, the number of atoms in the compound that reacts (the reactants and products) will have the same number
Reactants : Fe(s)+O₂(g)
Fe = 2 atoms
O = 3 x 2 = 6 atoms
Products : Fe₂O₃(s)
Fe = 2 x 2 = 4 atoms
O = 2 x 3 = 6 atoms
The reaction is not balanced because the number of Fe atoms is not the same
The balanced reaction should be:
4Fe(s)+3O₂(g)⇒2Fe₂O₃(s)
Answer: The ocean plays a key role in this vital cycle of water. The ocean holds 97% of the total water on the planet; 78% of global precipitation occurs over the ocean, and it is the source of 86% of global evaporation. ... Water evaporates from the surface of the ocean, mostly in warm, cloud-free subtropical seas.
Explanation:
Hope this helps!
Answer:
<h2>mass = 200.23 g</h2>
Explanation:
The density of a substance can be found by using the formula

Since we are finding the mass
<h3>mass = Density × volume</h3>
From the question
Density = 0.81 g/mL
volume = 247.2 mL
Substitute the values into the above formula and solve for the mass
mass = 0.81 × 247.2
= 200.232
We have the final answer as
<h3>mass = 200.23 g to 2 decimal places</h3>
Hope this helps you