CHEM 1010 CHPT 04

Which greenhouse gas listed has the highest molar mass?

CF2Cl2

Chemists use the ____ as a unit of amount of substance.

Mole

The molar mass of any substance is the mass of 1 ___ of the particles of that substance.

Mole

One ____ of any substance contains Avogadro's number of particles.

Mole or mol

Consider the balanced equation 2H2 + O2 > 2H2O. The coefficients correspond to the number of particles of each substance involved in the reaction, which is proportional to the ____ of each substance.

Number of moles

The chemistry of carbon-based compounds is called ____ chemistry.

Organic

A unit that contains two or more elements covalently bonded together but that has an overall charge is called a ____ ion. Many ____ compounds contain such units.

Polyatomic ; ionic

In a(n) ____ compound electrons are transferred from one atom or group of atoms to another. Conversely in a (n) ____ compound electrons are shared.

ionic ; covalent

Ice core data shows that atmospheric CO2 levels...

were relatively constant from the beginning of the last millennium until around 1800

Which of the following formulas for ionic compounds are correct?

• Ca3N2 • CaO

In chemistry, the mole ____.

• Indicates amount of substance. • Is abbreviated mol

Which of the following are considered possible effects of climate change?

• Rise in sea levels • An increase in the incidence of insect-borne diseases • Changes in freshwater distribution

Select the options that correctly reflect the mass ratios and mass percentages of the elements in SO3.

• The mass ratio of S is 0.400. • The mass percentage of O is 60.0%.

In the compound MgO, the Mg ion has a charge of ____, while the O ion has a charge of ____.

+2 ; -2

An atom may lose or gain electrons to form an ion. Match each description of ions and their charges correctly.

• an ion with more electrons than it's neutral atom is called an <> anion • an ion with fewer electrons than it's neutral atom is called a <> cation • the charge of an ion with more electrons than its neutral atom is <> negative • the charge of an ion with fewer electrons than its neutral atom is <> positive

Contrast weather and climate by matching each term to the correct definition

• weather <> describes events of relatively short duration, including daily high and low temperatures • climate <> describes regional events recorded over long periods

Which statement correctly describes the procedure used to predict the ion formed by a main-group element?

A metal loses enough electrons to attain the same number as it's nearest noble gas.

Which human activity has the GREATEST net effect on atmospheric CO2 levels?

Burning fossil fuels. Fossil fuels are burned for generation of electricity, transportation, and heating. The combined effect of these activities is far greater than the effect of any other human activity.

Match each compound correctly to its molar mass. (round all atomic masses red from the periodic table to one place after the decimal)

CCl4 <> 154.0 g/mol PF3 <> 88.0 g/mol SO2 <> 64.1 g/mol

When naming an ionic compound, the ____ is always named first. To name the anion, the root of the non-metal name is added to the suffix ____.

Cation ; ide

Match each element with the appropriate charge in its ionic form.

Cl <> -1 Sr <> +2 S <> -2 Al <> +3

In the compound CrCl3 ____.

Cl has a -1 charge. Cr has a +3 charge.

The most abundant isotope of ____ is the internationally accepted standard for determining atomic mass.

Carbon, C, Carbon-12, or carbon 12

All atomic masses are determined relative to the mass of an atom of ____.

Carbon-12

In the formation of ionic compounds a metal will ____ electrons and a nonmetal will ____ electrons to form an ion with the same number of electrons as the nearest ____ gas.

Lose ; Gain ; Noble

Match each element in the compound NH3 to its correct mass ratio and mass percentage.

Mass Ratio of N: 0.824 Mass Percent of N: 82.4 Mass Ratio of H: 0.176 Mass Percent of H: 17.6

Which of the following ion combinations will result in an ionic compound that has a balanced number of positive and negative charges?

Na+ and Br- Ca^2+ and 2 F- 2 Li+ and S^2-

Match each metal ion to the correct Roman numeral that would be used when naming an ionic a compound when appropriate.

• (III) <> Fe^3+ Iron is a transition metal with more than one oxidation state. the Roman numeral (III) indicates a 3+ charge. • (II) <> Cr^2+ Chromium is a transition metal with more than one oxidation state. The Roman numeral (II) indicates a +2 charge. • None Zn^2+ Zinc only forms one cation and therefore Roman numerals should not be used. • (I) Cu+ Copper is a transition metal with more than one oxidation state. the Roman numeral (I) indicates a +1 charge.

Which of the following options correctly interpret the information provided by the balanced equation CH4 + 2O2 > CO2 + 2H2O?

• 1 mole of CH4 produces 1 mole of CO2 when reacted with 2 miles of O2. • 15 mol of CH4 will produce 15 mol of CO2 when burned completely in O2 • 1 molecule of CH4 reacts with 2 molecules of O2

Which of the following options describe the correct format used to represent a chemical compound?

• The number of atoms / ions in the formula is indicated by a subscript. • In the formula of an ionic compound the cation is always placed first.

Which of the following statements correctly describe the mole?

• The number of particles in a mole is called Avogadro's number. • One mole of any substance contains 6.02 x 10^23

Which statements describe an ionic compound?

• Compounds formed when metals combine with non-metals. • Compounds that contain no molecules.

Match each type of bond to the correct description given.

• Covalent bond <> attraction between two nuclei and a shared pair of electrons. • Ionic bond <> attraction between opposite-charged ions.

Which of the following statements correctly describe ions?

• Ions are formed when atoms lose or gain electrons. • F- is an example of an anion.

Which of the following options correctly describe each type of chemical compound?

• Molecular compounds tend to contain non-metals only. • Non-metals combine with metals to form ionic compounds.

Which of the following human activities increase the levels of atmospheric CO2?

• Respiration • Replacing trees with cultivated crops • Burning fossil fuels

Which of the following options correctly describe a polyatomic ion?

• The atoms of a polyatomic ion are held together by covalent bonds. • The charge on a polyatomic ion belongs to the whole unit.

Which of the following options correctly describe the changes observed in global temperature over time?

• The average global temperature of the Earth has increased over the past century. • The average global temperature has increased over the same period as atmospheric CO2 levels have increased.

Which of the following options correctly describe how to name an ionic compound?

• The cation is named first and the anion second. • When naming the anionic portion of the ionic compound, the element name is changed to end in --ide.

Which of the following options correctly describe a polyatomic ion?

• The charge on a polyatomic ion belongs to the whole unit. • The atoms of a polyatomic in are held together by covalent bonds.

Consider the formula for the ionic compound Na2O. Which of the following statements correctly interpret this formula?

• The compound contains 2 Na+ ions for every O^2- ion. • The cation in this compound is Na+.

Which of the following correctly describe how Roman numerals are used in naming and writing chemical formulas?

• The ion designated Fe (III) has a charge of +3 • A Roman numeral is included for any metal that can form more than one monatomic cation.

Which of the following statements correctly describe molar mass?

• The molar mass of oxygen is 16.00 g/mol which means that 1 mole of oxygen atoms has a mass of 16.00 g • The periodic table can be used to calculate the molar mass of any substance • The molar mass of a molecular substance is the mass per mole of its molecules.