Question 1

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more chemical elements held together by chemical bonds.

Question 2

Which scientist's gold foil experiment led to the discovery of the atomic nucleus?

Accepted Answer

Ernest Rutherford

Question 3

What is the molar mass of carbon dioxide ($$CO_2$$)?

Accepted Answer

$$44\ \mathrm{g/mol}$$

Question 4

Which of the following is a homogeneous mixture?

Accepted Answer

Salt water

Question 5

A sample contains $$3.01 	imes 10$$^{23}$$ molecules of H_2O$. How many moles of water does this represent?

Accepted Answer

$$0.5$$ moles

Question 6

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 7

Which quantum number determines the shape of an atomic orbital?

Accepted Answer

Azimuthal quantum number ($$\ell)$$

Question 8

What is the correct electron configuration for magnesium ($$Mg$$, atomic number 12)?

Accepted Answer

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

Question 9

Which type of chemical bond involves the transfer of electrons from one atom to another?

Accepted Answer

Ionic bond

Question 10

Which property increases as the strength of intermolecular forces increases in a liquid?

Accepted Answer

Boiling point

Question 11

A reaction is carried out with $$100\ \mathrm{g} of$$ $$Na$$ and $$100\ \mathrm{g} of$$ $$Cl_2 to $$produce $$NaCl. $$Which is the limiting reagent?

Accepted Answer

$$Cl_2$$

Question 12

Which of the following best describes the VSEPR model?

Accepted Answer

It predicts the arrangement of electron pairs around a central atom to minimize repulsion.

Question 13

Which of the following is a combustion reaction?

Accepted Answer

$$CH_4 + 2O_2$$ \rightarrow $$CO_2 + 2H_2O$

Question 14

Which intermolecular force is present in all substances, but is the only one present in non-polar molecules?

Accepted Answer

Induced dipole-induced dipole (London dispersion)

Question 15

What is the formal charge on the oxygen atom in $$NO_2$$ with 6 valence electrons, 4 non-bonded electrons, and 4 bonded electrons?

Accepted Answer

$$0$$

Question 16

Which of the following best explains why gases are compressible?

Accepted Answer

Gas particles occupy a small fraction of the total volume.

Question 17

A $$1000\ \mathrm{L}$$ tank contains $$1000$$ moles of $$H_2 at$$ $$25^\circ C. $$What is the pressure in the tank? ($$R = 0.0821\ \mathrm{L\ atm\ $$mol^{-1}$$\ K$$^{-1}$$})$$

Accepted Answer

$$24.6\ \mathrm{atm}$$

Question 18

Which of the following molecules has a trigonal pyramidal molecular geometry?

Accepted Answer

$$NH_3$$

Question 19

Which of the following is NOT a property of an ideal gas according to kinetic molecular theory?

Accepted Answer

There are strong attractive forces between gas particles.

Question 20

Which of the following best describes the difference between a molecule and a compound?

Accepted Answer

A molecule consists of two or more atoms bonded together, while a compound consists of two or more different elements bonded together.

Foundations of Chemistry: Atoms, Elements, Compounds, and Chemical Reactions

Guida di studio - Domande di pratica

Study guide - Flashcard