Answer:
In the criss-cross method, the numerical value of the ion charge of the two atoms are crossed over, which becomes the subscript of the other ion. Using this technique, we will write the chemical formula of the given compounds.
Criss cross the absolute values to give Al2O3. To find the formula for magnesium oxide:- The oxidation number of Mg is +2 and oxygen is -2. Criss cross the absolute values to give Mg2O2In this example there is a common factor of 2 so divide by 2 to give MgO.
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Answer:

Explanation:
Balanced equation: CO(g) + H₂O(g) ⟶ CO₂(g) + H₂(g)
We can calculate the enthalpy change of a reaction by using the enthalpies of formation of reactants and products

(a) Enthalpies of formation of reactants and products

(b) Total enthalpies of reactants and products

(c) Enthalpy of reaction
The answer is option E. All of the above
Answer:
All liquids are fluids but not all fluids are liquids. Fluids basically describe anything that can flow as a result of a difference in pressure between two points. Liquids on the other hand are a subset of fluids. Liquids are the incompressible fluids. These are the fluids who's density does not change sharply with pressure.
Gases are also fluids, they form the compressible fluids. They do flow as a result of difference in pressure between two points but at the same time they can be compressed or expanded. Their density fluctuates with pressure.
Hence fluids consist of 2 mutually exclusive groups of compressible and incompressible fluids. Liquids are the incompressible fluids and hence form a subset of the more general term fluid.