Question

Question 28

MA₂B₂ is a molecule where M is the central atom bonded to 2 atoms of A and 2 atoms of B. The fact that it exists in only one form (no isomers) suggests its geometry is

Select one:

a. octahedral

b. square planar

c. tetrahedral

d. trigonal planar

Question 29

A compound is found to consist of 28.1% sodium, 13.2% boron and 58.7% oxygen. What is its simplest formula?

Select one:

a. NaBO₂

b. NaBO₃

c. Na₂B₄O₇

d. Na₃BO₃

Question 30

What mass of carbon is present in 0.500 mol of phenol (C₆H₅OH)?

Select one:

a. 94 g

b. 47 g

c. 36 g

d. 6 g

Question 31

A 4.000 g sample of an unknown metal, M, was completely burned in excess O₂ to yield 0.02225 mol of the metal oxide, M₂O₃. What is the metal?

Select one:

a. Y

b. Ca

c. Al

d. Sc

Question 32

What is the maximum mass in grams of aluminum chloride that could be obtained from 2.50 mol of barium chloride and excess aluminum sulfate? This is the balanced equation for the reaction: Al₂(SO₄)₃ + 3BaCl₂--> 3BaSO₄ + 2AlCl₃. BaCl₂molar mass is 208.3 g/mol and AlCl₃molar mass is 133.3 g/mol.

Select one:

a. 521 g

b. 334 g

c. 222 g

d. 55.8

Question 33

1.0 x 10^-5 g sample of a compound is known to contain 1.36 x 10¹⁷ molecules. This compound is

Select one:

a. CO₂

b. CH₄

c. NH₃

d. H₂O

Answer 1

Question 28

MA₂B₂ is a molecule where M is the central atom bonded to 2 atoms of A and 2 atoms of B. The fact that it exists in only one form (no isomers) suggests its geometry is

Select one:

a. octahedral

b. square planar

c. tetrahedral-------------answer

d. trigonal planar

Question 29

A compound is found to consist of 28.1% sodium, 13.2% boron and 58.7% oxygen. What is its simplest formula?

Select one:

a. NaBO₂

b. NaBO_{3-------------answer}

c. Na₂B₄O₇

d. Na₃BO₃

Question 30

What mass of carbon is present in 0.500 mol of phenol (C₆H₅OH)?

Select one:

a. 94 g------------------------------answer

b. 47 g

c. 36 g

d. 6 g

Question 31

A 4.000 g sample of an unknown metal, M, was completely burned in excess O₂ to yield 0.02225 mol of the metal oxide, M₂O₃. What is the metal?

Select one:

a. Y-------------answer

b. Ca

c. Al

d. Sc

Question 32

What is the maximum mass in grams of aluminum chloride that could be obtained from 2.50 mol of barium chloride and excess aluminum sulfate? This is the balanced equation for the reaction: Al₂(SO₄)₃ + 3BaCl₂--> 3BaSO₄ + 2AlCl₃. BaCl₂molar mass is 208.3 g/mol and AlCl₃molar mass is 133.3 g/mol.

Select one:

a. 521 g

Actually 533 g.

Three moles of BaCl2 produce two moles of AlCl3, so 6.00 mol of barium chloride produce 4.00 mol of aluminum chloride.
RMM of AlCl3 :3 x 35.4527 + 26.981538 = 133.339638 g/mol

4.00 x 133.339638 = 533.358552 g

Question 33

1.0 x 10^-5 g sample of a compound is known to contain 1.36 x 10¹⁷ molecules. This compound is

Select one:

a. CO_2--answer

b. CH₄

c. NH₃

d. H₂O