goles Test 81. The GFM of magnesium chloride, MgCl_(2) is: a. 5908g/mol b. 95.2g/mol C 125.8g/mol d. 76.4g/mol 82. What is the percent composition of aluminum in aluminum sulfat a. 54.0% b. 28.1% C. 15.8% d. 84.2% 83. How many grams are in 2.00 moles of sodium sulfate (Na_(2)SO_(4) a. 2849 b. 2389 C. 0.0141 g d. 0.0170 g 84. Which of the following is an empirical formula? a. CH_(3) b. C_(6)H_(12)O_(6) N_(2)O_(4) d. C_(5)H_(10) 85. How many grams are in 6.02times 10^23 molecules of CO_(2) a. 449 b. 2.64times 10^25g C. 7.319 d. 649 60 moles? Name

81. The molar mass of magnesium chloride, , is calculated by adding the molar masses of magnesium (Mg) and chlorine (Cl). The molar mass of Mg is 24.305 g/mol, and the molar mass of Cl is 35.453 g/mol. Since there are two chlorine atoms in , the molar mass is: Therefore, the correct answer is:b. 82. The percent composition of aluminum in aluminum sulfate, , is calculated by dividing the total mass of aluminum by the molar mass of aluminum sulfate and then multiplying by 100. The molar mass of aluminum is 26.98 g/mol, and the molar mass of aluminum sulfate is: The percent composition of aluminum is: Therefore, the correct answer is:c. 83. The molar mass of sodium sulfate, , is calculated by adding the molar masses of sodium (Na), sulfur (S), and oxygen (O). The molar mass of Na is 22.99 g/mol, the molar mass of S is 32.06 g/mol, and the molar mass of O is 16.00 g/mol. Since there are two sodium atoms, one sulfur atom, and four oxygen atoms in , the molar mass is: To find the mass of 2.00 moles of , we multiply the molar mass by the number of moles: Therefore, the correct answer is284984. An empirical formula represents the simplest whole-number ratio of atoms in a compound. Among the given options, is the simplest whole-number ratio of carbon (C) and hydrogen (H), making it an empirical formula.Therefore, the correct answer is:a. 85. To find the mass of molecules of , we first need to convert the number of molecules to moles using Avogadro's number, which is molecules/mol. Since the molar mass of is 44.01 g/mol, the mass of molecules of is:\[ \text{Mass