Q: A solution contains 485 mL of 0.208 M concentration. If you only have a 0.672 M stock solution, what volume of stock solution is needed to prepare the desired solution? Use $$M_1V_1 = M_2V_2.$$

$$V_1$$ = \frac{0.208 \times 485}{0.672} = 150.1\ mL$$

Question 1

What is the correct chemical name for NaBr according to the naming rules and the flowchart provided?

Accepted Answer

Sodium bromide

Question 2

Given the Lewis structure for SiCl4 (see image), what is the molecular geometry and why?

Accepted Answer

Tetrahedral, because there are four electron domains and four bonds around the central atom.

Question 3

What is the ground state electron configuration for a neutral sodium atom (Na)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^1$$

Question 4

Which of the following best describes the bond type between Na and F, given their electronegativity values (Na: 0.9, F: 4.0)?

Accepted Answer

Ionic, because $$\Delta EN = 3.1$$

Question 5

What is the correct formula for ammonium nitrate?

Accepted Answer

$$NH_4NO_3$$

Question 6

Given the Lewis structure for PI3 (see image), what is the molecular geometry and why?

Accepted Answer

Trigonal pyramidal, because there are three bonds and one lone pair on the central atom.

Question 7

Which molecule is nonpolar due to both its symmetry and its bond type, as shown in the provided images and descriptions?

Accepted Answer

CBr4

Question 8

What is the molecular geometry and polarity of CO2, based on its Lewis structure and shape diagram?

Accepted Answer

Linear and nonpolar

Question 9

A solution contains 485 mL of 0.208 M concentration. If you only have a 0.672 M stock solution, what volume of stock solution is needed to prepare the desired solution? Use $$M_1V_1 = M_2V_2.$$

Accepted Answer

$$V_1$$ = \frac{0.208 	imes 485}{0.672} = 150.1\ mL$$

Question 10

What is the molecular weight of sodium acetate ($$NaC_2H_3O_2$$)?

Accepted Answer

$$82.04\ g/mol$$

Question 11

Which experiment would best determine if an unknown substance is an electrolyte?

Accepted Answer

Dissolve the substance in water and test if the solution conducts electricity.

Question 12

Which of the following is a nonelectrolyte?

Accepted Answer

Sugar (C6H12O6)

Question 13

What is the electron configuration for $$O^{2-}$$?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$

Question 14

Which bond is the strongest and shortest among single, double, and triple bonds?

Accepted Answer

Triple bond

Question 15

According to the VSEPR model, what is the electron geometry of a molecule with three electron domains around the central atom?

Accepted Answer

Trigonal planar

Question 16

Which of the following mixtures is a colloid?

Accepted Answer

Milk

Question 17

What is the percent concentration (w/v) of a solution made by dissolving 10 g of NaCl in 100 mL of water?

Accepted Answer

$$10\%$$

Question 18

Which molecule is polar due to its asymmetrical shape, as shown in the provided diagrams?

Accepted Answer

SO2

Question 19

What is the correct name for PbI2 according to the naming flowchart?

Accepted Answer

Lead(II) iodide

Intro to Chemistry Exam 2 Study Guide & Practice Problems

Guida di studio - Domande di pratica

Study guide - Flashcard