Exam 3 Pretest

The number of electrons in an ion with 20 protons and an ionic charge of 2- is A) 24. B) 22. C) 20. D) 18. E) 16.

B

16) What is the correct formula for the oxide ion? A) O2- B) O C) O+ D) O2+ E) O3+

a

Avogadro's number is the number of A) particles in 1 mole of a substance. B) amu in 1 mole of a substance. C) grams in 1 mole of a substance. D) moles in 6.02 x 10^23 grams of an element. E) moles in 6.02 x 10^23 amu of an element.

a

The ability of an atom to attract the shared electrons in a covalent bond is its A) electronegativity. B) bonding ability. C) polarity. D) ionic character. E) nonpolarity.

a

The correct formula for the compound formed from Mg and S is A) MgS B) MgS2- C) Mg2S- D) Mg2S2- E) Mg2S3-

a

the molar mass of C3H8O2 is A) 76.0g B) 60.0g C)29.0g D)69.0g E)52.03g

a

) The name of the Cu+ ion is A) copper (II). B) copper (I). C) copper (III). D) copper. E) cuprum.

b

19) What is the correct formula for the iron (II) ion? A) Fe+ B) Fe2+ C) Fe3+ D) Fe2- E) Fe3-

b

Double and triple bonds form because A) the atoms involved have high electronegativities. B) single covalent bonds do not give all of the atoms in the molecule eight valence electrons. C) one of the atoms in the molecule has more than 8 valence electrons. D) the ions involved have charges larger than one. E) there is at least one hydrogen atom involved in the bond.

b

How many electrons will chlorine gain or lose when it forms an ion? A) lose 1 B) gain 1 C) lose 7 D) gain 2 E) lose 3

b

How many grams of glucose (C6H12O6) are in 3.55 moles of glucose? A) 180 g B) 639 g C) 103 g D) 426 g E) 50.7 g

b

How many moles of water, H2O, are present in 75.0 g H2O? A) 4.41 moles B) 4.17 moles C) 75.0 moles D) 7.50 moles E) 1.35 x 10^3 moles

b

What is the formula of carbon tetraiodide? A) CI B) CI4 C) C4I D) CI3 E) C2I4

b

Which of the following compounds contains a polar covalent bond? A) NaF B) HCl C) Br2 D) MgO E) O2

b

Which of the following correctly gives the best coefficients for the reaction below? N2H4 + H2O2 --> N2 + H2O A) 1, 1, 1, 1 B) 1, 2, 1, 4 C) 2, 4, 2, 8 D) 1, 4, 1, 4 E) 2, 4, 2, 4

b

A(n) ________ is the smallest neutral unit of two or more atoms held together by a covalent bond. A) ionic compound B) nucleus C) molecule D) formula E) unit

c

Elements in group 2A(2) of the periodic table form ions with a charge of A) 1+. B) 1-. C) 2+. D) 3+. E) 0.

c

The ion of aluminum is A) Al+ . B) Al2+ C) Al3+ D) Al3- E) Al2-

c

What is the ionic charge of an ion with 18 protons and 15 electrons? A) 1+ B) 2+ C) 3+ D) 2- E) 3-

c

Which of the following compounds contains an ionic bond? A) NH3 B) H2O C) CaO D) H2 E) Ch4

c

Which one of the following compounds contains an ion with a 3+ charge? A) KCl B) Na2O C) FeCl3 D) CuCl E) MgCl2

c

the molar mass of Calcuim Hydroxide, Ca(OH)2, is\ A)58.1g B)57.1g C)74.1g D)14.2g E)38.0g

c

0.400 mole of sucrose, C12H22O11 contains ______ C atoms A) 12 B) 6.02 x 10^23 C) 5.02 x 10^22 D) 2.89 x 10^24 E) 4.80

d

1 mole of neon has a mass of A) 6.02 x 10^23 g B) 14.0g C) 10.0g D)20.2 g E) 30.2g

d

1) The octet rule indicates that A) all of the noble gases have eight total electrons. B) all of the shells in an atom hold a maximum of 8 electrons. C) all of the Group A elements have 8 valence electrons. D) atoms lose, gain, or share valence electrons to have 8 valence electrons. E) the noble gases react with other compounds to get 8 valence electrons.

d

17) The compound MgCl2 is named A) magnesium chlorine. B) magnesium dichloride. C) magnesium (II) chloride. D) magnesium chloride. E) dimagnesium chloride.

d

3) How many electrons will aluminum gain or lose when it forms an ion? A) lose 1 B) gain 5 C) lose 2 D) lose 3 E) gain 1

d

5) To form an ion, a sodium atom A) gains one electron. B) gains two electrons. C) loses seven electrons. D) loses one electron. E) loses two electrons.

d

A chemical equation is balanced when A) the total number of molecules is the same in reactants and products. B) the total number of ions is the same in reactants and products. C) the sum of the coefficients of the reactants is equal to the sum of the coefficients of the products. D) the number of atoms of each element is the same in reactants and products. E) the charge on each atom is the same in reactants and products.

d

According to naming rules, the types of compound that use prefixes in their names are A) ionic compounds. B) ionic compounds involving transition metals. C) polyatomic ions. D) covalent compounds. E) compounds that contain polyatomic ions.

d

In a molecule with covalent bonding, A) oppositely charged ions are held together by strong electrical attractions. B) atoms of metals form bonds to atoms of nonmetals. C) atoms of different metals form bonds. D) atoms are held together by sharing electrons. E) atoms of noble gases are held together by attractions between oppositely charged ions.

d

One mole of particles of any substance contains how many particles? A) 10^6 B) 3 x 10^-10 C) 3 x 10^10 D) 6.02 x10^23 E) 6.02 x 10^-23

d

What coefficient is placed in front of to complete the balancing of the following equation? C5H8 + ?O2 --> 5CO2 + 4H2O A) 1 B) 3 C) 5 D) 7 E) 9

d

Which of the following gives the balanced equation for this reaction? K3PO4+Ca(NO3)2 ---> Ca3(PO4)2 + KNO3 A) KPO4 + CaNO3 + KNO3 B) K3PO4 + Ca(NO3)2 --> Ca3(PO4)2 + 3KNO3 C) 2K3PO4 + Ca(NO3)2 --> Ca3(PO4)2 + 6KNO 3 D) 2KPO4 + 3Ca(NO3)2 --> Ca3(PO4)2 + 6KNO3 E) K3PO4 + Ca(NO3)2 --> Ca3(PO4)2 + KNO3

d

) Which one of the following elements forms two or more ions with different ionic charges? A) K B) F C) Ca D) O E) Fe

e

2) In ionic compounds, ________ lose their valence electrons to form positively charged ________. A) metals, anions B) nonmetals, cations C) metals, polyatomic ions D) nonmetals, anions E) metals, cations

e

4) What is the symbol for the ion with 19 protons and 18 electrons? A) F+ B) F- C) Ar+ D) K- E) K+

e

An anion always A) has a positive charge. B) contains a group of two or more atoms with a positive charge. C) contains a metal and a nonmetal. D) forms covalent bonds. E) has a negative charge.

e

An ionic compound A) has a net positive charge. B) has a net negative charge. C) contains only cations. D) contains only anions. E) has a net charge of zero.

e

In a covalently bonded molecule, the number of electrons that an atom shares with others is usually equal to the number of electrons A) in the atom. B) in its nucleus. C) in all the atoms. D) in its ion. E) needed to give it a noble gas arrangement.

e

One mole of copper(II) sulfate, CuSO4, contains________ O atoms. A) 4 B) 6.02 x 10^23 C) 1.51 x 10^22 D) 2.41 x 10^23 E) 2.41 x 10^24

e

The correct formula for a compound formed from the elements Al and O is A) AlO B) Al2O C) Al3O2- D) AlO3- E) Al2O3-

e

The correct name for the compound N2O3 is A) nitrogen oxide. B) nitrogen trioxide. C) dinitride trioxide. D) dinitrogen oxide. E) dinitrogen trioxide.

e

The correct name of the compound NCl3 is A) nitrogen chloride. B) trinitrogen chloride C) nitrogen(III) chloride. D) nickel chloride. E) nitrogen trichloride.

e

The name of Al2(SO4)3 is A) aluminum(III) sulfate. B) dialuminum trisulfate. C) dialuminum sulfate. D) dialuminum trisulfide. E) aluminum sulfate.

e

What is the correct formula for iron (III) sulfide? A) Fe2S2 B) Fe2S C) FeS D) FeS2 E) Fe2S3

e

What is the molar mass of Mg3(PO4)2, a substance formerly used in medicine as an antacid? A) 71.3 g B) 118.3 g C) 150.3 g D) 214.3 g E) 262.9 g

e

Which of the following elements does NOT exist as a diatomic molecule? A) hydrogen B) nitrogen C) chlorine D) oxygen E) carbon

e

Which of the following substances contains a nonpolar covalent bond? A) H2O B) NaCl C) NH3 D) MgF2 E) N2

e

(H2O) according to the following reaction. Answer the following question(s) about this reaction. C5H12 + ?O2 --> ?CO2 + ?H2O What is the coefficient for oxygen in the balanced equation? A) 2 B) 4 C) 5 D) 6 E) 8 What is the coefficient for carbon dioxide in the balanced equation? A) 2 B) 4 C) 5 D) 6 E) 8

e, c