5. (03.09 mc)\ndana wants to determine the molar mass of magnesium hydroxide, mg(oh)₂. which calculation…

5. (03.09 mc)\ndana wants to determine the molar mass of magnesium hydroxide, mg(oh)₂. which calculation should she use? (2 points)\n(atomic number of mg) + (2 x atomic number of o) + (2 x atomic number of h)\n2 x (atomic number of mg + atomic number of o + atomic number of h)\n(molar mass of mg) + (2 x molar mass of o) + (2 x molar mass of h)\n2 x (molar mass of mg + molar mass of o + molar mass of h)

5. (03.09 mc)\ndana wants to determine the molar mass of magnesium hydroxide, mg(oh)₂. which calculation should she use? (2 points)\n(atomic number of mg) + (2 x atomic number of o) + (2 x atomic number of h)\n2 x (atomic number of mg + atomic number of o + atomic number of h)\n(molar mass of mg) + (2 x molar mass of o) + (2 x molar mass of h)\n2 x (molar mass of mg + molar mass of o + molar mass of h)

Answer

Explanation:

Step1: Recall molar - mass calculation rule

The molar mass of a compound is the sum of the molar masses of its constituent atoms. For $Mg(OH)_2$, it contains 1 magnesium atom ($Mg$), 2 oxygen atoms ($O$), and 2 hydrogen atoms ($H$).

Step2: Write the molar - mass formula

The molar mass of $Mg(OH)_2$ is calculated as the molar mass of $Mg$ plus 2 times the molar mass of $O$ plus 2 times the molar mass of $H$, i.e., (molar mass of $Mg$)+(2×molar mass of $O$)+(2×molar mass of $H$).

Answer:

(molar mass of $Mg$)+(2×molar mass of $O$)+(2×molar mass of $H$)