Question 1

What is the mass (in kg)of 6.89 × 10²⁵molecules of CO₂? The molar mass of CO₂ is 44.01 g mol^-1.

Accepted Answer

First, we need to convert the given number of molecules into moles:

6.89 × 10^21 molecules COS = (6.89 × 10^21 molecules COS) / (6.022 × 10^23 molecules/mol) = 0.0114 mol COS

Next, we can use the molar mass of COS to convert moles into grams:

0.0114 mol COS = (0.0114 mol COS) × (44.01 g/mol) = 0.502 g COS

Finally, we can convert grams into kilograms:

0.502 g COS = (0.502 g COS) / (1000 g/kg) = 0.000502 kg COS

Multiplying this mass by the number of molecules we started with, we get:

(0.000502 kg COS/molecule) × (6.89 × 10^21 molecules COS) = 3.46 kg

Rounding to two significant figures, the answer is 5.04 kg.

Question 2

Identify an ether.

Accepted Answer

The answer of Identify an ether.
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Question 3

Identify the name for the compound Fe(C₂H₃O₂)₂.

Accepted Answer

The compound contains Fe(II) and the anion is made up of acetate (C2H3O2-), which is denoted as (OOCCH3)- in the formula. Therefore, the compound is iron(II) acetate.

Question 4

Calculate the molar mass of H₂CO₃.

Accepted Answer

The answer of Calculate the molar mass of H₂CO₃. ...

Question 5

What is the mass of 9.44 × 10²⁴ molecules of NO₂? The molar mass of NO₂ is 46.01 g mol^-1.

Accepted Answer

First, we need to calculate the mass of one mole of NOS1U1B12S1U1B0:

46.01 g/mol

Then, we can use this molar mass to convert the number of molecules into grams:

9.44 × 10S1U1P124S1S1P0 molecules x (1 mol/6.022 × 10S2U1P23S1S1P0 molecules) x (46.01 g/mol) = 720.9 g

Rounded to three significant figures, the answer is 721 g. Therefore, the correct choice is C.

Question 6

Calculate the molar mass for Mg(ClO₄)₂.

Accepted Answer

The answer of Calculate the molar mass for Mg(ClO₄)₂. ...

Question 7

Identify a hydrocarbon.

Accepted Answer

The answer of Identify a hydrocarbon.
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Question 8

How many millimoles of Ca(NO₃)₂ contain 4.78 × 10²² formula units of Ca(NO₃)₂? The molar mass of Ca(NO₃)₂ is 164.10 g mol^-1.

Accepted Answer

The answer of How many millimoles of Ca(NO₃)₂ contain 4.78...

Question 9

How many moles of C₃H₈ contain 9.25 × 10²⁴ molecules of C₃H₈?

Accepted Answer

The answer of How many moles of C₃H₈ contain 9.25...

Question 10

Calculate the molar mass of Ca₃(PO₄)₂.

Accepted Answer

First, we need to break down the chemical formula into its individual elements and their respective quantities:
- Ca: 1
- S: 2
- U: 2
- B: 26
- P: 1
- O: 14

Next, we need to look up the atomic masses of each element from the periodic table and multiply it by its respective quantity:
- Ca: 1 x 40.08 g/mol = 40.08 g/mol
- S: 2 x 32.06 g/mol = 64.12 g/mol
- U: 2 x 238.03 g/mol = 476.06 g/mol
- B: 26 x 10.81 g/mol = 281.06 g/mol
- P: 1 x 30.97 g/mol = 30.97 g/mol
- O: 14 x 15.99 g/mol = 223.86 g/mol

Finally, we add up all the individual masses:
40.08 g/mol + 64.12 g/mol + 476.06 g/mol + 281.06 g/mol + 30.97 g/mol + 223.86 g/mol = 1116.15 g/mol

However, we need to subtract the total mass of the positively charged ions (U and Ca) and add the total mass of the negatively charged ions (P and O):
1116.15 g/mol - (2 x 238.03 g/mol + 1 x 40.08 g/mol) + (1 x 30.97 g/mol + 14 x 15.99 g/mol) = 310.18 g/mol

Question 11

Which of the following compounds is ethanol?

Accepted Answer

Ethanol has a hydroxyl (-OH) group attached to a carbon chain, which is represented by the molecular formula CH3CH2OH. Option B is the only choice that has this specific arrangement of atoms, with -OH attached to the second carbon atom in the chain.

Question 12

Identify a carboxylic acid.

Accepted Answer

The molecule with the COOH functional group is E, which is the only choice with a carboxylic acid group.

Question 13

How many molecules of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g mol^-1.

Accepted Answer

The answer of How many molecules of N₂O₄ are in...

Question 14

Identify an amine.

Accepted Answer

The compound CH₃CH₂NH₂ contains an amine functional group, which is characterized by the nitrogen atom with one or more organic substituents. In this case, the amine nitrogen has two organic substituents (CH₃ and CH₂) and an additional hydrogen atom (not included in the molecular formula).

Question 15

Calculate the molar mass of Al(C₂H₃O₂)₃.

Accepted Answer

The answer of Calculate the molar mass of Al(C₂H₃O₂)₃. ...

Question 16

Which of the following is one possible form of pentane?

Accepted Answer

The answer of Which of the following is one possible...

Question 17

How many moles of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g mol^-1.

Accepted Answer

To calculate the number of moles of N₂O₄, we need to use the following formula: moles = mass / molar mass Given: mass = 76.3 g molar mass = 92.02 g/mol Substituting the values in the formula, we get: moles = 76.3 g / 92.02 g/mol ≈ 0.829 mol Therefore, the best choice is E, as it is the only option closest to 0.829 mol.

Question 18

Which of the following is a formula for the compound iridium(III)bromide tetrahydrate?

Accepted Answer

The answer of Which of the following is a formula...

Question 19

How many C₂H₄ molecules are contained in 45.8 mg of C₂H₄? The molar mass of C₂H₄ is 28.05 g mol^-1.

Accepted Answer

The answer of How many C₂H₄ molecules are contained in...

Question 20

Which of the following is a formula for the compound disulfur tetrafluoride?

Accepted Answer

The answer of Which of the following is a formula...

Quiz 3: Molecules, Compounds, and Nomenclature

What is the mass (in kg) of 6.89 × 10²⁵molecules of CO₂? The molar mass of CO₂ is 44.01 g mol^-1.

Identify an ether.

Identify the name for the compound Fe(C₂H₃O₂) ₂.

Calculate the molar mass of H₂CO₃.

What is the mass of 9.44 × 10²⁴ molecules of NO₂? The molar mass of NO₂ is 46.01 g mol^-1.

Calculate the molar mass for Mg(ClO₄) ₂.

Identify a hydrocarbon.

How many millimoles of Ca(NO₃) ₂ contain 4.78 × 10²² formula units of Ca(NO₃) ₂? The molar mass of Ca(NO₃) ₂ is 164.10 g mol^-1.

How many moles of C₃H₈ contain 9.25 × 10²⁴ molecules of C₃H₈?

Calculate the molar mass of Ca₃(PO₄) ₂.

Which of the following compounds is ethanol?

Identify a carboxylic acid.

How many molecules of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g mol^-1.

Identify an amine.

Calculate the molar mass of Al(C₂H₃O₂) ₃.

Which of the following is one possible form of pentane?

How many moles of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g mol^-1.

Which of the following is a formula for the compound iridium(III) bromide tetrahydrate?

How many C₂H₄ molecules are contained in 45.8 mg of C₂H₄? The molar mass of C₂H₄ is 28.05 g mol^-1.

Which of the following is a formula for the compound disulfur tetrafluoride?

Quiz 3: Molecules, Compounds, and Nomenclature

What is the mass (in kg) of 6.89 × 1025 molecules of CO2? The molar mass of CO2 is 44.01 g mol-1.

Identify an ether.

Identify the name for the compound Fe(C2H3O2) 2.

Calculate the molar mass of H2CO3.

What is the mass of 9.44 × 1024 molecules of NO2? The molar mass of NO2 is 46.01 g mol-1.

Calculate the molar mass for Mg(ClO4) 2.

Identify a hydrocarbon.

How many millimoles of Ca(NO3) 2 contain 4.78 × 1022 formula units of Ca(NO3) 2? The molar mass of Ca(NO3) 2 is 164.10 g mol-1.

How many moles of C3H8 contain 9.25 × 1024 molecules of C3H8?

Calculate the molar mass of Ca3(PO4) 2.

Which of the following compounds is ethanol?

Identify a carboxylic acid.

How many molecules of N2O4 are in 76.3 g N2O4? The molar mass of N2O4 is 92.02 g mol-1.

Identify an amine.

Calculate the molar mass of Al(C2H3O2) 3.

Which of the following is one possible form of pentane?

How many moles of N2O4 are in 76.3 g N2O4? The molar mass of N2O4 is 92.02 g mol-1.

Which of the following is a formula for the compound iridium(III) bromide tetrahydrate?

How many C2H4 molecules are contained in 45.8 mg of C2H4? The molar mass of C2H4 is 28.05 g mol-1.

Which of the following is a formula for the compound disulfur tetrafluoride?

What is the mass (in kg) of 6.89 × 10²⁵molecules of CO₂? The molar mass of CO₂ is 44.01 g mol^-1.

Identify the name for the compound Fe(C₂H₃O₂) ₂.

Calculate the molar mass of H₂CO₃.

What is the mass of 9.44 × 10²⁴ molecules of NO₂? The molar mass of NO₂ is 46.01 g mol^-1.

Calculate the molar mass for Mg(ClO₄) ₂.

How many millimoles of Ca(NO₃) ₂ contain 4.78 × 10²² formula units of Ca(NO₃) ₂? The molar mass of Ca(NO₃) ₂ is 164.10 g mol^-1.

How many moles of C₃H₈ contain 9.25 × 10²⁴ molecules of C₃H₈?

Calculate the molar mass of Ca₃(PO₄) ₂.

How many molecules of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g mol^-1.

Calculate the molar mass of Al(C₂H₃O₂) ₃.

How many moles of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g mol^-1.

How many C₂H₄ molecules are contained in 45.8 mg of C₂H₄? The molar mass of C₂H₄ is 28.05 g mol^-1.