Question 1

A rock is placed in a graduated cylinder containing water, as shown in the images. The initial water level is 17.0 mL and the final water level is 29.5 mL. If the mass of the rock is 78.45 g, what is the density of the rock in $$\mathrm{g/mL}$$? (Give your answer to the correct number of significant figures.)

Accepted Answer

$$1.36\ \mathrm{g/mL}$$

Question 2

What is the name of the laboratory glassware shown in the second image?

Accepted Answer

Erlenmeyer flask

Question 3

Based on the standard curve shown in the third image, what is the absorbance of a solution with a concentration of $$8.73\ \mathrm{mg/L}$$? (Use the equation $$y = 0.1054x + 0.0533$$ and give your answer to three significant figures.)

Accepted Answer

$$0.974$$

Question 4

A buret is used in a titration experiment. The initial reading is $$9.35\ \mathrm{mL}$$ and the final reading is $$24.18\ \mathrm{mL}. $$How much liquid was dispensed? (Give your answer to the correct number of significant figures.)

Accepted Answer

$$14.83\ \mathrm{mL}$$

Question 5

Which of the following best describes the function of an Erlenmeyer flask in a chemistry laboratory?

Accepted Answer

It is used for mixing, heating, and storing liquids.

Question 6

A buret is classified as which type of glassware?

Accepted Answer

TD only (To Deliver)

Question 7

If the volume of water displaced by a rock is $$12.5\ \mathrm{mL}$$ and the mass of the rock is $$78.45\ \mathrm{g}$$, what is the density of the rock in $$\mathrm{kg/m^3$}$$? (1 $$\mathrm{g/mL} = 1000\ \mathrm{kg/m^3$})$$

Accepted Answer

$$6276\ \mathrm{kg/m^3$}$$

Question 8

Which variable is the independent variable in the standard curve graph shown in the third image?

Accepted Answer

Concentration

Question 9

A student uses a buret to deliver a solution for a titration. If the buret is read incorrectly from above the meniscus instead of at eye level, what type of error is most likely to occur?

Accepted Answer

Systematic error

Question 10

If a solution has an absorbance of $$1.20$$ according to the standard curve equation $$y = 0.1054x + 0.0533$$, what is the concentration in $$\mathrm{mg/L}$$? (Give your answer to three significant figures.)

Accepted Answer

$$10.9\ \mathrm{mg/L}$$

Question 11

Which of the following is the best reason for using an Erlenmeyer flask instead of a beaker when swirling a solution during a titration?

Accepted Answer

It minimizes the risk of spillage due to its narrow neck.

Question 12

A student records the following buret readings: initial $$10.00\ \mathrm{mL}$$, final $$25.00\ \mathrm{mL}. $$What is the volume of liquid delivered, and how many significant figures should the answer have?

Accepted Answer

$$15.00\ \mathrm{mL}$$, 3 significant figures

General Chemistry 1A Sample Exam – Step-by-Step Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard