A. time/mass b. number/time c. energy/time d. time/energy
Note that the density of pure aluminum is 2.7 g/cm³ (from tables).
Given:
m = 39.0 g, the mass of the metal
V = 10.0 cm³, the density of the metal
By definition, the density of the metal is
density = mass/volume
= (39.0 g)/(10.0 cm³)
= 3.9 g/cm³
Answer:
The calculated density is not equal to 2.7 g/cm³, therefore the metal sphere is not made of pure aluminum.
The number of moles of sodium dichromate from the number of moles of oxygen atoms can be determined through stoichiometry. Using the molecular formula of the compound, Na2Cr2O7, 1 mole of the compound contains 7 moles of oxygen. Hence, 14 moles O2*(1 mole Na2Cr2O7/ 7 mole O2) is equal to 2 moles <span>Na2Cr2O7.</span>
Answer:
Explanation:
The number of moles of solute is equal to product of the molar concentration (molarity) and the volume (in liters) of solution.
Since the volumes and the molar concentrations of the<em> NaOH </em>and <em>HCl </em>solutions mixed are equal, each one of them contributes the same number of moles of solute.
Since every mol of NaOH produces one mol of OH⁻ ions and every mol of HCl produces one mol of H⁺ ion, the number of moles of OH ⁻ and H⁺ in solution are equal.
Thus, OH⁻ and H⁺ ions will be neutralized by the reaction:
- OH⁻ (aq) + H⁺ (aq) ⇄ H₂O (l)
Which is strongly shifted to the right and has <em>neutral pH</em>.
Hence, you conclude that the approximate <em>pH of the solution is neutral.</em>
Answer:
Explanation:
Hello,
In this case, for the given chemical reaction:
The standard entropy change is computed by subtracting the products standard enthalpy and the reactants standard enthalpy considering each species stoichiometric coefficients:
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