Q: If you have $$125\ \mathrm{g} of$$ $$\mathrm{C$$_{12}$$H_{16}O$$}$$, how many molecules are present? (M$$_{\mathrm{C_{12}$$H_{16}O$$}} = 176.25\ \mathrm{g/mol}$$, N_A = 6.022$$ \times $$10^{23})$$

$$4.27 \times 10$$^{23}$$ molecules

Q: Which calculation would you use to determine the number of carbon atoms in a sample of $$\mathrm{C$$_{12}$$H_{16}O$$}$?

$$N_{\text{C atoms}} = N_{\text{molecules}} \times 12$$

Question 1

Which of the following best describes the concept of sustainability as defined by the United Nations Brundtland Commission?

Accepted Answer

Meeting the needs of the present without compromising the ability of future generations to meet their own needs.

Question 2

In the context of sustainable chemistry, which of the following is NOT a major contribution of chemists to a warming world?

Accepted Answer

Increasing the use of non-renewable resources.

Question 3

Which statement about 'chemical-free' products is scientifically accurate?

Accepted Answer

Nothing can be truly chemical-free; all matter is made of chemicals.

Question 4

Which of the following is NOT one of the three main green chemistry metrics discussed in the unit?

Accepted Answer

Activation Energy

Question 5

Given the reaction $$\mathrm{C$$_{12}$$H_{16}O$$} + \mathrm{C_4H_7ClO_2} \rightarrow \mathrm{$$C_{16}H$$_{22}$$O_3$$} + \mathrm{HCl}$$, what is the molar mass of $$\mathrm{$$C_{12}H$$_{16}$$O}$$?

Accepted Answer

$$176.25\ \mathrm{g/mol}$$

Question 6

If you have $$125\ \mathrm{g} of$$ $$\mathrm{C$$_{12}$$H_{16}O$$}$$, how many molecules are present? (M$$_{\mathrm{C_{12}$$H_{16}O$$}} = 176.25\ \mathrm{g/mol}$$, N_A = 6.022$$ 	imes $$10^{23})$$

Accepted Answer

$$4.27 	imes 10$$^{23}$$ molecules

Question 7

In the balanced equation $$\mathrm{C$$_{13}$$H_{17}N$$} + 2\mathrm{H_2O} \rightarrow \mathrm{$$C_{13}H$$_{18}$$O_2$$} + \mathrm{$$NH_3$$}$, what is the sum of the lowest whole number stoichiometric coefficients?

Accepted Answer

5

Question 8

What is the theoretical yield (in grams) of $$\mathrm{C$$_{13}$$H_{18}O$$}$$ in Step 3 of the Ibuprofen synthesis if there is 1.05$$\ \mathrm{g}$$ of $$\mathrm{$$C_{16}H$$_{22}$$O_3$$}$$ and excess water? (M$$_{\mathrm{C_{16}$$H_{22}O_3$}} = 262.34\ \mathrm{g/mol}$$, $$M_{\mathrm{C_{13}H$$_{18}$$O}} = 190.29\ \mathrm{g/mol})$$

Accepted Answer

$$0.762\ \mathrm{g}$$

Question 9

In a reaction where $$115.25\ \mathrm{g} of$$ $$\mathrm{C$$_{13}$$H_{19}O$$}$$ and 5.75$$\ \mathrm{g}$$ of $$\mathrm{H_3NO}$$ are used to produce 17.00$$\ \mathrm{g}$$ of $$\mathrm{$$C_{13}H$$_{19}$$NO}$$, what is the percent yield? ($$M_{\mathrm{C_{13}H$$_{19}$$NO}} = 205.30\ \mathrm{g/mol}$)

Accepted Answer

47.57%

Question 10

Which of the following is a correct definition of Atom Economy?

Accepted Answer

The percentage of reactant atoms incorporated into the desired product.

Question 11

Which green chemistry principle is most directly targeted by reducing the E Factor in a chemical process?

Accepted Answer

Waste prevention

Question 12

A process has an atom economy of 77% and an E Factor of 3. What does this suggest about the process compared to one with an atom economy of 50% and an E Factor of 10?

Accepted Answer

It is greener, producing less waste and using more reactant atoms efficiently.

Question 13

Which of the following is NOT a goal of implementing green chemistry?

Accepted Answer

Maximizing hazardous waste production

Question 14

Which metric is calculated as the ratio of the total mass of waste to the mass of the desired product?

Accepted Answer

E Factor

Question 15

What is the volume of $$\mathrm{CO_2$}$$ gas produced at $$1.00\ \mathrm{bar}$$ and $$25^\circ\mathrm{C} if$$ $$2.68 	imes 10$$^{-3}$$ mol $$\mathrm{$$CO_2$$}$$ is generated? (R = 0.0831451$$\ \mathrm{L\cdot bar\cdot $$K^{-1}$$\cdot $$mol^{-1}$$}$$, T = 298$$\ \mathrm{K}$$)

Accepted Answer

$$0.0664\ \mathrm{L}$$

Question 16

Which of the following is a key difference between the prior and current synthesis of Ibuprofen?

Accepted Answer

The current synthesis uses fewer steps and produces less waste.

Question 17

Which of the following is NOT a use of solvents in chemistry?

Accepted Answer

Increasing the number of atoms in a molecule

Question 18

Which calculation would you use to determine the number of carbon atoms in a sample of $$\mathrm{C$$_{12}$$H_{16}O$$}$?

Accepted Answer

$$N_{	ext{C atoms}} = N_{	ext{molecules}} 	imes 12$$

Question 19

Which of the following is NOT a step in performing a Life Cycle Assessment (LCA) for a chemical product?

Accepted Answer

Ignoring the disposal and recycling phase

Unit 1 – Introduction to Sustainable Chemistry: Stoichiometry, Green Chemistry, and Metrics

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