Chemistry Regents Practice Questions

Which of the following atoms has the greatest nuclear charge? 1. Al 2. Ar 3. Si 4. Na

2. Ar

All isotopes of a given element must have the same 1. Atomic mass 2. Atomic number 3. Mass number 4. Number of neutrons

2. Atomic number

All samples of an element are composed of atoms with the same 1. Atomic mass 2. Atomic number 3. Number of nucleons 4. Number of neutrons

2. Atomic number

What type of bonding is present within a network solid? 1. Hydrogen 2. Covalent 3. Ionic 4. Metallic

2. Covalent

The electrons in a bond between two iodine atoms (I2) are shared 1. Equally, and the resulting bond is polar 2. Equally, and the resulting bond is nonpolar 3. Unequally, and the resulting bond is polar 4. Unequally, and the resulting bond is nonpolar

2. Equally, and the resulting bond is nonpolar

Which equation illustrates conservation of mass? 1. H2 + Cl2 → HCl 2. H2 + Cl2 → 2HCl 3. H2 +O2 → H2O 4. H2 + O2 → 2H2O

2. H2 + Cl2 → 2HCl

Which is an empirical formula? 1. H2O2 2. H2O 3. C2H2 4. C3H6

2. H2O

Which three elements have the most similar chemical properties? 1. Ar, Kr, Br 2. K, Rb, Cs 3. B, C, N 4. O, N, Si

2. K, Rb, Cs

When ionic bonds are formed, metallic atoms tend to 1. Lose electrons and become negative ions 2. Lose electrons and become positive ions 3. Gain electrons and become negative ions 4. Gain electrons and become positive ions

2. Lose electrons and become positive ions

Which compound contains ionic bonds? 1. N2O 2. Na2O 3. CO 4. CO2

2. Na2O

When a bond is formed, energy is (released/absorbed) When a bond is broken, energy is (released/absorbed)

Released Absorbed

Name the following groups from the PT: 1. 1: 2. 2: 3. 17: 4. 18:

1: Alkali metals 2: Alkaline earth metals 17: Halogens 18: Noble gases

To which group do the alkaline earth metals belong? 1. 1 2. 2 3. 11 4. 12

2. 2

If 75.0% of the isotopes of an element have a mass of 35.0 amu and 25.0% of the isotopes have a mass of 37.0 amu, what is the atomic mass of the element? 1. 35.0 amu 2. 35.5 amu 3. 36.0 amu 4. 37.0 amu

2. 35.5 amu

What type of bond exists in a molecule of hydrogen iodide? 1. A polar covalent bond with an electronegativity difference of zero 2. A polar covalent bond with an electronegativity difference between zero and 1.7 3. A nonpolar covalent bond with an electronegativity difference of zero 4. A nonpolar covalent bond with an electronegativity difference between zero and 1.7

2. A polar covalent bond with an electronegativity difference between zero and 1.7

When the equation _____C8H16 + _____ O2 → ____ CO2 + H2O is correctly balanced using the smallest whole number coefficient, the coefficient of O2 is 1. 1 2. 8 3. 12

0 C8H16 + 12O2 → 8CO2 + 8H2O 3. 12

How many Sig figs are in the following values? 1. 0.002 g 2. 12000 L 3. 2.45 × 10^2m 4. 103040 g

1. 1 2. 2 3. 3 4. 5

In a sample of the element potassium, each atom has 1. 19 protons 2. 20 neutrons 3. 39 protons and neurons 4. 39 neutrons

1. 19 protons

Calculate the following: 1. 53.2 °C 2. 783.4 K

1. 326.2 K 2. 510.4 °C

Calculate to the correct # of Sig figs: 1. 3.5674+0.022+1.20000+3.2 2. 3.4 × 1.204 × 0.03

1. 8.0 1 sig fig 2. 0.1 1 sig fig

A characteristic of most nonmetallic solids is that they are 1. Brittle 2. Ductile 3. Malleable 4. Conductors of electricity

1. Brittle

Which is the correct formula for carbon (II) oxide? 1. CO 2. CO2 3. C2O 4. C2O3

1. CO

Which element in Group 1 has the greatest tendency to lose an electron? 1. Cesium 2. Rubidium 3. Potassium 4. Sodium

1. Cesium

Which element can form a chloride with a general formula of MCl2 or MCl3? 1. Fe 2. Al 3. Mg 4. Zn

1. Fe

Most nonmetals have the properties of 1. High ionization energy and poor electrical conductivity 2. High ionization energy and good electrical conductivity 3. Low ionization energy and poor electrical conductivity 4. Low ionization energy and good electrical conductivity

1. High ionization energy and poor electrical conductivity

A white crystalline salt conducts electricity when it is melted and when it is dissolved in water. Which type of bond does this salt contain? 1. Ionic 2. Metallic 3. Covalent 4. Network

1. Ionic

Rutherford's gold foil experiment illustrated that the atom 1. Is mostly empty space 2. Is definitely packed with electrons 3. Cannot be penetrated by any radiation 4. Contains a negatively charged nucleus

1. Is mostly empty space

Which statement best describes an electron? 1. It has a smaller mass than a proton and a negative charge. 2. It has a smaller mass than a proton and a positive charge. 3. It has a greater mass than a proton and a negative charge 4. It has a greater mass than a proton and a positive charge

1. It has a smaller mass than a proton and a negative charge

Which particle contains the fewest number of electrons? 1. K 2. K+ 3. Cl 4. Cl-

1. K

Neutral atoms of the same element can differ in their number of 1. Neutrons 2. Positrons 3. Protons 4. Electrons

1. Neutrons

Which term refers to the region of an atom where an electron is most likely to be found? 1. Orbital 2. Orbit 3. Quantum 4. Spectrum

1. Orbital

Which particles account for most of the mass of the atom? 1. Protons and neutrons 2. Protons and electrons 3. Neutrons and electrons 4. Neutrons and positrons

1. Protons and neutrons

The characteristic bright-line spectrum of sodium is produced when its electrons 1. Return to lower energy levels 2. Jump to higher energy levels 3. Are lost by the neutral atoms 4. Are gained by the neutral atoms

1. Return to lower energy levels

Compared to the the entire atom, the nucleus of the atom is 1. Smaller and contains most of the atom's mass 2. Smaller and contains little of the atom's mass 3. Larger and contains most of the atom's mass 4. Larger and contains most of the atom's mass

1. Smaller and contains most of the atom's mass

In an experiment, alpha particles were used to bombard gold foil. As a result of this experiment, the conclusion was made that the nucleus of an atom is 1. Smaller than the atom and positively charged 2. Smaller than the atom and negatively charged 3. Larger than the atom and positively charged 4. Larger than the atom and negatively charged

1. Smaller than the atom and positively charged

An example of a heterogeneous mixture is 1. Soil 2. Sugar 3. Carbon monoxide 4. Carbon dioxide

1. Soil

Which factor distinguishes a metallic bond from an ionic bond or a covalent bond? 1. The mobility of electrons 2. The mobility of protons 3. The equal sharing of electrons 4. The unequal sharing of electrons

1. The mobility of electrons

The atomic number of any atom is equal to the number of 1. Neutrons in the atom, only 2. Protons in the atom, only 3. Neutrons plus protons in the atoms 4. Protons plus electrons in the atom

2. Protons in the atom, only

What is the percent by mass of sulfur in sulfur dioxide? (Separate sheet of paper) 1. 32 2. 33 3. 50 4. 67

3. 50

What is the mass number of an atom which contains 28 protons, 28 electrons, and 34 neutrons? 1. 28 2. 56 3. 62 4. 90

3. 62

The formula for calcium cyanide is 1. CaCN2 2. CaSCN2 3. Ca(CN)2 4. Ca(SCN)2

3. Ca(CN)2

Two atoms with an electronegativity difference of 0.4 form a bond that is 1. Ionic, because electrons are shared 2. Ionic, because electrons are transferred 3. Covalent, because electrons are shared 4. Covalent, because electrons are transferred

3. Covalent, because electrons are shared

Which element is a member of halogen family? 1. K 2. B 3. I 4. S

3. I

Which substance can be decomposed by chemical change? 1. Beryllium 2. Boron 3. Methanol 4. Magnesium

3. Methanol

The ability to conduct electricity in the solid state is a characteristic of metallic bonding. This characteristic is best explained by the presence of 1. High ionization energies 2. High electronegativities 3. Mobile electrons 4. Mobile protons

3. Mobile electrons

In an equation, which symbol would indicate a mixture? 1. NH3(s) 2. NH3(l) 3. NH3(aq) 4. NH3(g)

3. NH3(aq)

Neutral atoms of 35^Cl and 37^Cl differ with respect to their number of 1. Electrons 2. Protons 3. Neutrons 4. Positrons

3. Neutrons

In a nonpolar covalent bond, electrons are 1. Located in a mobile "sea" shared by many ions 2. Transferred from one atom to another 3. Shared equally by two atoms 4. Shared unequally by two atoms

3. Shared equally by two atoms

Which group contains an element that is liquid at STP? 1. 1 2. 2 3. 16 4. 17

4. 17

What is the percent by mass of nitrogen in the compound NH4NO3 (formula mass = 80.)? (Separate sheet of paper) 1. 5.7% 2. 18% 3. 29% 4. 35%

4. 35%

What is the total number of valence electrons in a carbon atom in the ground state? 1. 6 2. 2 3. 12 4. 4

4. 4

An atom of carbon- 14 contains 1. 8 protons, 6 neutrons and 6 electrons 2. 6 protons, 6 neutrons and 8 electrons 3. 6 protons, 8 neutrons and 8 electrons 4. 6 protons, 8 neutrons and 6 electrons

4. 6 protons, 8 neutrons and 6 electrons

A substance was found to be a soft, nonconducting solid at room temperature. The substance is most likely 1. A molecular solid 2. A network solid 3. A metallic solid 4. An ionic solid

4. An ionic solid

When an atom of chlorine forms an ionic bond with an atom of sodium, the atom of chlorine 1. Loses an electron 2. Loses a proton 3. Becomes an ion with a smaller radius than the atom of chlorine 4. Becomes an ion with a larger radius than the atom of chlorine

4. Becomes an ion with a larger radius than the atom of chlorine

Which formula represents a substance that contains covalent bonds? 1. LiCl 2. CaCl2 3. K2O 4. CO2

4. CO2

An experiment using alpha particles to bombard a thin sheet of gold foil indicated that most of the volume of the atoms in the foil is taken up by 1. Electrons 2. Protons 3. Neutrons 4. Empty space

4. Empty space

Compared to the average kinetic energy of one mole of water at 298 K is energy of 1 mole of water at 298 K is 1. The same and the number of molecules is the same 2. The same, but the number of molecules is greater 3. Greater and the number of molecules is greater 4. Greater, but the number of molecules is the same

4. Greater, but the number of molecules is the same

Which statement describes a chemical property of the element iodine? 1. Its crystals are metallic gray. 2. It dissolves in alcohol. 3. It forms a violet-colored gas. 4. It reacts with hydrogen to form a gas.

4. It reacts with hydrogen to form a gas

Which ion has the same electron configuration as a H- ion? 1. Cl- 2. F- 3. K+ 4. Li+

4. Li+

Which is a characteristic of all mixtures? 1. They are homogeneous. 2. They are heterogeneous. 3. Their composition is a definite ratio. 4. Their composition can be varied.

4. Their composition can be varied.

What is the density of an object with a mass of 34g and a volume of 13cm^3? (Separate sheet of paper)

D=2.6g/cm^3

What is the mass of an object with a density of 5.7g/cm^3 and a volume of 48 ml? (Separate sheet of paper)

M=273.6g

What is the volume of a liquid with a density of 1.5 g/ml and a mass of 78g? (Separate sheet of paper)

V=52ml

The density of Lead is 11.4 g/ml. If a sample of Lead has a mass of 91 g, what is the volume of this sample of Lead? (Separate sheet of paper)

V=8.0ml

Given the equation: _____FeCl2 + _____Na2CO3 → ____FeCO3 + _____NaCl. When the equation is correctly balanced using the smallest whole numbers, the coefficient of NaCl is 1. 6 2. 2 3. 3 4. 4

_____ FeCl2 + Na2CO3 → ______ FeCO3 + 2NaCl 2. 2