Question 1

Question

A)Which statement describes the quantities that can be found using the number of moles?(1 point)
Responses

It can be used to find the number of molecules, atoms, or ions.
It can be used to find the number of molecules, atoms, or ions.

It can be used to find the number of molecules or atoms, but not ions.
It can be used to find the number of molecules or atoms, but not ions.

It can be used to find the number of molecules, but not atoms or ions.
It can be used to find the number of molecules, but not atoms or ions.

It can be used to find the number of molecules or ions, but not atoms.
It can be used to find the number of molecules or ions, but not atoms.
Question 2
A)A scientist uses 3 g of water (H2O) in an experiment. Which option describes the first step in calculating the number of molecules in 3 g of water?(1 point)
Responses

Apply Avogadro's number, 6.022×1023
.
Apply Avogadro's number, 6 point 0 2 2 times 10 to the 23th power.

Calculate the number of moles of water.
Calculate the number of moles of water.

Identify the molar masses of H and O.
Identify the molar masses of H and O.

Determine the molar mass of water.
Determine the molar mass of water.
Question 3
A)The molar mass of ammonia (NH3) is 17.03 g/mol. Which expression correctly shows how to determine the number of moles of ammonia equivalent to 5 g?(1 point)
Responses

5 g×1 mol17.03 g
5 g×1 mol17.03 g

5 g×17.03 mol1 g
5 g×17.03 mol1 g

5 g×17.03 g1 mol
5 g×17.03 g1 mol

5 g×1 g17.03 mol
5 g×1 g17.03 mol
Question 4
A)How many molecules of carbon dioxide (CO2) are there in 0.450 mol of carbon dioxide?(1 point)
Responses

5.42×1023
5 point 4 2 times 10 to the 23th power

1.34×1024
1 point 3 4 times 10 to the 24th power

2.71×1023
2 point 7 1 times 10 to the 23th power

6.02×1023
6 point 0 2 times 10 to the 23th power
Question 5
A)When magnesium chloride (MgCl2) is dissolved in water, which statement must be true?(1 point)
Responses

The mass of the Mg2+ ions and the mass of the Cl– ions must each be equal to the mass of MgCl2.
The mass of the Mg 2+ ions and the mass of the Cl – ions must each be equal to the mass of MgCl 2 .

The number of moles of the Mg2+ ions and the number of moles of the Cl– ions must each be equal to the number of moles of MgCl2.
The number of moles of the Mg 2+ ions and the number of moles of the Cl – ions must each be equal to the number of moles of MgCl 2 .

The sum of the mass of the Mg2+ ions and the mass of the Cl– ions must be equal to the mass of MgCl2.
The sum of the mass of the Mg 2+ ions and the mass of the Cl – ions must be equal to the mass of MgCl 2 .

The sum of the number of moles of the Mg2+ ions and the number of moles of the Cl– ions must be

Answer 1

Here are the answers to your questions:

Question 1: A) Which statement describes the quantities that can be found using the number of moles?

• Correct Response: It can be used to find the number of molecules, atoms, or ions.

Question 2: A) A scientist uses 3 g of water (H2O) in an experiment. Which option describes the first step in calculating the number of molecules in 3 g of water?

• Correct Response: Determine the molar mass of water.

Question 3: A) The molar mass of ammonia (NH3) is 17.03 g/mol. Which expression correctly shows how to determine the number of moles of ammonia equivalent to 5 g?

• Correct Response: 5 g × 1 mol / 17.03 g

Question 4: How many molecules of carbon dioxide (CO2) are there in 0.450 mol of carbon dioxide?

• Correct Response: 2.71 × 10^23

Question 5: A) When magnesium chloride (MgCl2) is dissolved in water, which statement must be true?

• Correct Response: The sum of the mass of the Mg2+ ions and the mass of the Cl– ions must be equal to the mass of MgCl2.

Please let me know if you need further explanations or have more questions!