Question 1

A patient’s bone density is measured as 1.15 g/cm$$^3. If $$the normal range is 1.20–1.35 g/cm$$^3$$, what percentage below the lower limit is the patient’s bone density? Use the formula: 
$$	ext{Percent difference} = \frac{	ext{Normal} - 	ext{Measured}}{	ext{Normal}} 	imes 100\%$$

Accepted Answer

4.2\%

Question 2

Which of the following is an exact number?

Accepted Answer

There are 12 eggs in a dozen.

Question 3

Which of the following correctly represents the electron configuration for a neutral atom of magnesium (Mg, atomic number 12)?

Accepted Answer

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

Question 4

Which of the following elements is most likely to form a +2 ion?

Accepted Answer

Ca

Question 5

What is the correct formula for ammonium sulfate?

Accepted Answer

$$(NH_4$)_2SO_4$$

Question 6

Which of the following molecules is nonpolar?

Accepted Answer

$$CO_2$$

Question 7

A reaction has the following balanced equation:
$$2H_2 + O_2$ \rightarrow 2H_2O
If $$you start with 4.0 mol $$H_2$$ and 2.0 mol $$O_2$$, what is the limiting reactant?

Accepted Answer

Neither; both are in exact stoichiometric ratio

Question 8

A sample of gas occupies 2.50 L at 1.00 atm and 300 K. What will be its volume at 2.00 atm and 300 K? (Assume ideal gas behavior.)
Use $$P_1V_1 = P_2V_2.$$

Accepted Answer

1.25 L

Question 9

Which of the following solutions is saturated?

Accepted Answer

A solution in which no more solute can dissolve at a given temperature.

Question 10

How many grams of NaCl are needed to prepare 250 mL of a 0.200 M NaCl solution? ($$M = \frac{mol}{L}$$, molar mass NaCl = 58.44 g/mol)

Accepted Answer

2.92 g

Question 11

Which change will shift the equilibrium to the right for the reaction below?
$$N_2(g) + 3H_2(g$$) \rightleftharpoons 2NH_3(g) + heat$$

Accepted Answer

Remove $$NH_3$$

Question 12

Which of the following is a Brønsted-Lowry acid?

Accepted Answer

$$H_2SO_4$$

Question 13

What is the conjugate base of $$HCO_3$$^-$$?

Accepted Answer

$$CO_3$$^{2-}$$

Question 14

A weak acid, HA, has a dissociation constant $$K_a = 1.8 	imes 10$$^{-5}$$. Which statement is true?

Accepted Answer

HA only partially ionizes in water.

Question 15

Which of the following is the correct name for $$HNO_3$$?

Accepted Answer

Nitric acid

Question 16

A solution has a $$[H^+] of$$ $$1.0 	imes 10$$^{-8}$$ M. What is the pH of the solution?
Use pH$$ = -\log[H^+]$$.

Accepted Answer

8.0

Question 17

Which of the following is a correct Lewis structure for methane ($$CH_4$$)?

Accepted Answer

A central C atom with four single bonds to four H atoms.

Question 18

Which of the following is a decomposition reaction?

Accepted Answer

$$2H_2O_2 \rightarrow 2H_2O + O_2$

Question 19

Which of the following statements about electronegativity is correct?

Accepted Answer

Electronegativity increases across a period and decreases down a group.

Question 20

A nurse needs to prepare 100 mL of a 0.50 M glucose solution from a 2.0 M stock solution. What volume of stock solution is required?
Use $$C_1V_1 = C_2V_2.$$

Accepted Answer

25 mL

CHEM 1050 Final Exam Study Guide: Key Topics and Concepts

Guida di studio - Domande di pratica

Study guide - Flashcard