Question 1

Iron reacts with oxygen to form iron(III)oxide according to the chemical equation below.What is the theoretical yield of product when 5.00 grams of Fe react with excess O₂? [Molar masses: Fe,55.85 g/mol; O,16.00g/mol] 4Fe(s)+ 3O₂(g)→ 2Fe₂O₃(s)

Accepted Answer

The answer of Iron reacts with oxygen to form iron(III)oxide...

Question 2

Magnesium hydroxide,Mg(OH)₂,as "Milk of Magnesia" can be used to neutralize excess stomach acid,represented by HCl(aq)according to the chemical equation below. Mg(OH)₂(s)+ 2HCl(aq)→ MgCl₂(aq)+ 2H₂O(l) When 5.00 g of HCl are combined with an excess of Mg(OH)₂,what mass of MgCl₂ can be produced? [Molar masses: H,1.01 g/mol; O,16.00 g/mol; Mg,24.31 g/mol; Cl,35.45 g/mol]

Accepted Answer

The answer of Magnesium hydroxide,Mg(OH)₂,as "Milk of Magnesia" can be...

Question 3

Cisplatin is a chlorine-containing chemotherapy agent with the formula Pt(NH₃)₂Cl₂.What is the mass of one mole of cisplatin?

Accepted Answer

The answer of Cisplatin is a chlorine-containing chemotherapy agent with...

Question 4

The fluoride rinse in dental offices usually contains sodium fluoride.Sodium fluoride can be prepared from the reaction between sodium metal and fluorine gas.Which of the following properly represents the balanced chemical equation for this reaction?

Accepted Answer

The correct balanced chemical equation for the reaction between sodium metal and fluorine gas to produce sodium fluoride is 2Na(s) + F2(g) → 2NaF(s), which matches choice E.

Question 5

To convert a given number of moles into the number of atoms,one would multiply by which of the following factors?

Accepted Answer

To convert moles to atoms, you multiply by Avogadro's number, which is 6.022 × 10^23 atoms/mol.

Question 6

What is the mass of one mole of carbon atoms?

Accepted Answer

The mass of one mole of carbon atoms is approximately 12.01 grams, which corresponds to the atomic mass of carbon on the periodic table, expressed in grams per mole.

Question 7

The average mass of one atom of copper is 63.55 amu.What is the mass of Avogadro's number of copper atoms?

Accepted Answer

The mass of Avogadro's number of atoms of any element (expressed in grams) is equal to the atomic mass of that element (expressed in atomic mass units, amu). Since the atomic mass of copper is 63.55 amu, the mass of Avogadro's number of copper atoms is 63.55 grams.

Question 8

A sample of sulfur contains 1.81 × 10²⁴ atoms of sulfur.How many moles of sulfur does this represent?

Accepted Answer

The answer of A sample of sulfur contains 1.81 ×...

Question 9

What is the mass of 3.01 mol of sulfur atoms?

Accepted Answer

The molar mass of sulfur is approximately 32.06 g/mol. Therefore, the mass of 3.01 mol of sulfur atoms is 3.01 mol × 32.06 g/mol = 96.5 g.

Question 10

When the equation below is balanced with the lowest possible whole number coefficients,what is the sum of the coefficients? Ca(s)+ HCl(g)→ CaCl₂(s)+ H₂(g)

Accepted Answer

The balanced chemical equation is Ca(s) + 2HCl(g) → CaCl2(s) + H2(g), with coefficients 1, 2, 1, and 1, respectively. The sum of these coefficients is 1 + 2 + 1 + 1 = 5.

Question 11

Dinitrogen monoxide,or laughing gas (N₂O),is used as a dental anesthetic and as an aerosol propellant.How many molecules of N₂O are present in a 12.6 g sample of the compound?

Accepted Answer

The molar mass of N2O is 44.01 g/mol. So, 12.6 g of N2O is equal to 12.6 g / 44.01 g/mol = 0.286 mol. 1 mol of any substance contains 6.022 × 10^23 molecules. So, 0.286 mol of N2O contains 0.286 mol * 6.022 × 10^23 molecules/mol = 1.72 × 10^23 molecules.

Question 12

How many atoms of sulfur are present in a 155 g sample of sulfur? [Molar mass: S,32.06 g/mol]

Accepted Answer

To find the number of atoms, first calculate the number of moles of sulfur: 155 g / 32.06 g/mol = 4.834 moles. Then, multiply by Avogadro's number (6.022 × 10^23 atoms/mol) to get the number of atoms: 4.834 moles × 6.022 × 10^23 atoms/mol = 2.91 × 10^24 atoms.

Question 13

How is the reaction shown below best classified? 2HgO(s)→ 2Hg(l)+ O₂(g)

Accepted Answer

This reaction is a decomposition reaction because a single compound (HgO) breaks down into simpler substances (Hg and O2).

Question 14

What mass of sodium hydroxide is necessary to react with a solution containing 73.00 g HCl,according to the chemical equation below? [Molar masses: NaOH,39.99 g/mol; HCl,36.45 g/mol] NaOH(aq)+ HCl(aq)→ NaCl(aq)+ H₂O(l)

Accepted Answer

The balanced chemical equation is:NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)From the equation, we can see that 1 mole of NaOH reacts with 1 mole of HCl.The molar mass of NaOH is 39.99 g/mol, and the molar mass of HCl is 36.45 g/mol.Therefore, the mass of NaOH required to react with 73.00 g of HCl is:mass of NaOH = (73.00 g HCl) × (1 mol HCl / 36.45 g HCl) × (1 mol NaOH / 1 mol HCl) × (39.99 g NaOH / 1 mol NaOH)= 80.09 g NaOHTherefore, the correct answer is A.

Question 15

How is the reaction shown below best classified? 2NaCl(s)+ F₂(g)→ 2NaF(s)+ Cl₂(g)

Accepted Answer

This reaction is a single-replacement reaction where fluorine (F2) replaces chlorine (Cl) in sodium chloride (NaCl) to form sodium fluoride (NaF) and chlorine gas (Cl2).

Question 16

How is the reaction shown below best classified? Ca(s)+ 2HCl(aq)→ CaCl₂(g)+ H₂(g)

Accepted Answer

This reaction is a single-replacement reaction, where calcium (Ca) replaces hydrogen (H) in hydrochloric acid (HCl), resulting in calcium chloride (CaCl2) and hydrogen gas (H2).

Question 17

Diamond is a pure form of the element carbon.If a 2 carat diamond has a mass of 0.396 g,how many carbon atoms are contained in this diamond?

Accepted Answer

The answer of Diamond is a pure form of the...

Question 18

How many moles of Au atoms are present in one ounce of pure gold? [1 oz = 28.4 g]

Accepted Answer

To find the number of moles of Au atoms in one ounce of pure gold, we use the formula: moles = mass (g) / molar mass (g/mol). The molar mass of gold (Au) is approximately 197 g/mol. Given 1 oz = 28.4 g, the calculation is 28.4 g / 197 g/mol = 0.144 mol.

Question 19

What is the mass of a 0.150 mole sample of sulfur?

Accepted Answer

The answer of What is the mass of a 0.150...

Question 20

Lithium oxide can be produced by the reaction shown below.If a manufacturing company wants to make 25.0 g of Li₂O,what mass of Li is necessary? [Molar masses: Li,6.94 g/mol; O,16.00 g/mol] 4Li(s)+ O₂(g)→ 2Li₂O(s)

Accepted Answer

First, calculate the molar mass of $Li_2O$: $2 \times 6.94 + 16.00 = 29.88 \, \text{g/mol}$. To produce 25.0 g of $Li_2O$, we use the ratio from the balanced equation, which shows 4 moles of Li are needed to produce 2 moles of $Li_2O$. Thus, for 25.0 g of $Li_2O$, the moles of $Li_2O$ are $25.0 \, \text{g} / 29.88 \, \text{g/mol} = 0.8367 \, \text{moles}$. Since 2 moles of $Li_2O$ require 4 moles of Li, 0.8367 moles of $Li_2O$ require $0.8367 \times 2 = 1.6734$ moles of Li. The mass of Li required is $1.6734 \, \text{moles} \times 6.94 \, \text{g/mol} = 11.6 \, \text{g}$.

Quiz 4: Calculations, chemical Changes, and the Chemical Equation

Iron reacts with oxygen to form iron(III) oxide according to the chemical equation below.What is the theoretical yield of product when 5.00 grams of Fe react with excess O₂? [Molar masses: Fe,55.85 g/mol; O,16.00g/mol] 4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)

Cisplatin is a chlorine-containing chemotherapy agent with the formula Pt(NH₃) ₂Cl₂.What is the mass of one mole of cisplatin?

The fluoride rinse in dental offices usually contains sodium fluoride.Sodium fluoride can be prepared from the reaction between sodium metal and fluorine gas.Which of the following properly represents the balanced chemical equation for this reaction?

To convert a given number of moles into the number of atoms,one would multiply by which of the following factors?

What is the mass of one mole of carbon atoms?

The average mass of one atom of copper is 63.55 amu.What is the mass of Avogadro's number of copper atoms?

A sample of sulfur contains 1.81 × 10²⁴ atoms of sulfur.How many moles of sulfur does this represent?

What is the mass of 3.01 mol of sulfur atoms?

When the equation below is balanced with the lowest possible whole number coefficients,what is the sum of the coefficients? Ca(s) + HCl(g) → CaCl₂(s) + H₂(g)

Dinitrogen monoxide,or laughing gas (N₂O) ,is used as a dental anesthetic and as an aerosol propellant.How many molecules of N₂O are present in a 12.6 g sample of the compound?

How many atoms of sulfur are present in a 155 g sample of sulfur? [Molar mass: S,32.06 g/mol]

How is the reaction shown below best classified? 2HgO(s) → 2Hg(l) + O₂(g)

What mass of sodium hydroxide is necessary to react with a solution containing 73.00 g HCl,according to the chemical equation below? [Molar masses: NaOH,39.99 g/mol; HCl,36.45 g/mol] NaOH(aq) + HCl(aq) → NaCl(aq) + H₂O(l)

How is the reaction shown below best classified? 2NaCl(s) + F₂(g) → 2NaF(s) + Cl₂(g)

How is the reaction shown below best classified? Ca(s) + 2HCl(aq) → CaCl₂(g) + H₂(g)

Diamond is a pure form of the element carbon.If a 2 carat diamond has a mass of 0.396 g,how many carbon atoms are contained in this diamond?

How many moles of Au atoms are present in one ounce of pure gold? [1 oz = 28.4 g]

What is the mass of a 0.150 mole sample of sulfur?

Lithium oxide can be produced by the reaction shown below.If a manufacturing company wants to make 25.0 g of Li₂O,what mass of Li is necessary? [Molar masses: Li,6.94 g/mol; O,16.00 g/mol] 4Li(s) + O₂(g) → 2Li₂O(s)

Quiz 4: Calculations, chemical Changes, and the Chemical Equation

Iron reacts with oxygen to form iron(III) oxide according to the chemical equation below.What is the theoretical yield of product when 5.00 grams of Fe react with excess O2? [Molar masses: Fe,55.85 g/mol; O,16.00g/mol] 4Fe(s) + 3O2(g) → 2Fe2O3(s)

Cisplatin is a chlorine-containing chemotherapy agent with the formula Pt(NH3) 2Cl2.What is the mass of one mole of cisplatin?

The fluoride rinse in dental offices usually contains sodium fluoride.Sodium fluoride can be prepared from the reaction between sodium metal and fluorine gas.Which of the following properly represents the balanced chemical equation for this reaction?

To convert a given number of moles into the number of atoms,one would multiply by which of the following factors?

What is the mass of one mole of carbon atoms?

The average mass of one atom of copper is 63.55 amu.What is the mass of Avogadro's number of copper atoms?

A sample of sulfur contains 1.81 × 1024 atoms of sulfur.How many moles of sulfur does this represent?

What is the mass of 3.01 mol of sulfur atoms?

When the equation below is balanced with the lowest possible whole number coefficients,what is the sum of the coefficients? Ca(s) + HCl(g) → CaCl2(s) + H2(g)

Dinitrogen monoxide,or laughing gas (N2O) ,is used as a dental anesthetic and as an aerosol propellant.How many molecules of N2O are present in a 12.6 g sample of the compound?

How many atoms of sulfur are present in a 155 g sample of sulfur? [Molar mass: S,32.06 g/mol]

How is the reaction shown below best classified? 2HgO(s) → 2Hg(l) + O2(g)

What mass of sodium hydroxide is necessary to react with a solution containing 73.00 g HCl,according to the chemical equation below? [Molar masses: NaOH,39.99 g/mol; HCl,36.45 g/mol] NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

How is the reaction shown below best classified? 2NaCl(s) + F2(g) → 2NaF(s) + Cl2(g)

How is the reaction shown below best classified? Ca(s) + 2HCl(aq) → CaCl2(g) + H2(g)

Diamond is a pure form of the element carbon.If a 2 carat diamond has a mass of 0.396 g,how many carbon atoms are contained in this diamond?

How many moles of Au atoms are present in one ounce of pure gold? [1 oz = 28.4 g]

What is the mass of a 0.150 mole sample of sulfur?

Lithium oxide can be produced by the reaction shown below.If a manufacturing company wants to make 25.0 g of Li2O,what mass of Li is necessary? [Molar masses: Li,6.94 g/mol; O,16.00 g/mol] 4Li(s) + O2(g) → 2Li2O(s)

Iron reacts with oxygen to form iron(III) oxide according to the chemical equation below.What is the theoretical yield of product when 5.00 grams of Fe react with excess O₂? [Molar masses: Fe,55.85 g/mol; O,16.00g/mol] 4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)

Cisplatin is a chlorine-containing chemotherapy agent with the formula Pt(NH₃) ₂Cl₂.What is the mass of one mole of cisplatin?

A sample of sulfur contains 1.81 × 10²⁴ atoms of sulfur.How many moles of sulfur does this represent?

When the equation below is balanced with the lowest possible whole number coefficients,what is the sum of the coefficients? Ca(s) + HCl(g) → CaCl₂(s) + H₂(g)

Dinitrogen monoxide,or laughing gas (N₂O) ,is used as a dental anesthetic and as an aerosol propellant.How many molecules of N₂O are present in a 12.6 g sample of the compound?

How is the reaction shown below best classified? 2HgO(s) → 2Hg(l) + O₂(g)

What mass of sodium hydroxide is necessary to react with a solution containing 73.00 g HCl,according to the chemical equation below? [Molar masses: NaOH,39.99 g/mol; HCl,36.45 g/mol] NaOH(aq) + HCl(aq) → NaCl(aq) + H₂O(l)

How is the reaction shown below best classified? 2NaCl(s) + F₂(g) → 2NaF(s) + Cl₂(g)

How is the reaction shown below best classified? Ca(s) + 2HCl(aq) → CaCl₂(g) + H₂(g)

Lithium oxide can be produced by the reaction shown below.If a manufacturing company wants to make 25.0 g of Li₂O,what mass of Li is necessary? [Molar masses: Li,6.94 g/mol; O,16.00 g/mol] 4Li(s) + O₂(g) → 2Li₂O(s)