Chap 3 Chem

if the theoretical yield is 66.3 and the actual yield is 63.7 what is the percentage yield

96%

A sample of glucose, C6H12O6, contains 1.210×1021 carbon atoms. How many molecules of glucose does it contain?

2.017×1020

Na2SiO3(s)+8HF(aq)→H2SiF6(aq)+2NaF(aq)+3H2O(l) How many moles of HF are needed to react with 0.260 mol of Na2SiO3?

2.08

A sample of glucose, C6H12O6, contains 1.210×1021 carbon atoms. How many atoms of hydrogen does it contain?

2.420×1021

A sample of glucose, C6H12O6, contains 1.210×1021 carbon atoms. How many moles of glucose does it contain?

3.349×10−4

Number of molecules in 8.437×10−2 mol C6H6.

5.081×1022

A sample of glucose, C6H12O6, contains 1.210×1021 carbon atoms. What is the mass of this sample in grams?

6.028×10−2

how many molecules per mole are there

6.02x10^23

Na2SiO3(s)+8HF(aq)→H2SiF6(aq)+2NaF(aq)+3H2O(l) How many grams of NaF form when 0.580 mol of HF reacts with excess Na2SiO3?

6.09

O3(g)+2NaI(aq)+H2O(l)→O2(g)+I2(s)+2NaOH(aq) How many grams of sodium iodide are needed to remove 1.3 mg of O3

8.1×10−3

molecular formula Empirical formula C2H4O, molar mass = 176.0 g/mol Express your answer as a chemical formula.

C8H16O4

empirical and molecular formulas Styrene, a compound substance used to make Styrofoam® cups and insulation, contains 92.3% C and 7.7% H by mass and has a molar mass of 104 g/mol.

CH, C8H8

molecular formula Empirical formula CHO2, molar mass = 90.0 g/mol Express your answer as a chemical formula.

C2H2O4

The characteristic odor of pineapple is due to ethyl butyrate, a compound containing carbon, hydrogen, and oxygen. Combustion of 1.95 mg of ethyl butyrate produces 4.42 mg of CO2 and 1.81 mg of H2O. What is the empirical formula of the compound?

C3H6O

empirical and molecular formulas Caffeine, a stimulant found in coffee, contains 49.5% C, 5.15% H, 28.9% N, and 16.5% O by mass and has a molar mass of 195 g/mol.

C4H5N2O,C8H10N4O2

combination reaction

a chemical change in which two or more substances react to form a single new substance

decomposition reaction

a reaction in which a single compound breaks down to form two or more simpler substances

combustion reaction

always contain O2 as a reactant and CO2 and H2O as products

2NaOH(s)+CO2(g)→Na2CO3(s)+H2O(l) 1.86 mol NaOH and 1.00 mol CO2 are allowed to react How many moles of the excess reactant remain after the completion of the reaction?

0.07

4NH3(g)+5O2(g)→4NO(g)+6H2O(g) In a certain experiment, 2.10 g of NH3 reacts with 3.85 g of O2. How many grams of the excess reactant remain after the limiting reactant is completely consumed?

0.461

Na2SiO3(s)+8HF(aq)→H2SiF6(aq)+2NaF(aq)+3H2O(l) How many grams of Na2SiO3 can react with 0.770 g of HF?

0.587

2NaOH(s)+CO2(g)→Na2CO3(s)+H2O(l) 1.86 mol NaOH and 1.00 mol CO2 are allowed to react How many moles of Na2CO3 can be produced?

0.93

O3(g)+2NaI(aq)+H2O(l)→O2(g)+I2(s)+2NaOH(aq) How many moles of sodium iodide are needed to remove 5.45×10−6 mol O3?

1.09×10−5

Mass (in grams) of 1.00×10−2 mol of CdS.

1.44g

Number of moles (n) of NH4Cl in 96.6 g of this substance

1.81 mol

2C8H18(l)+25O2(g)→16CO2(g)+18H2O(g) How many moles of O2 are needed to burn 1.40 mol of C8H18?

17.5

4NH3(g)+5O2(g)→4NO(g)+6H2O(g) In a certain experiment, 2.10 g of NH3 reacts with 3.85 g of O2. How many grams of NO and of H2O form

2.89,2.60

C3H6(g)+O2(g)→CO2(g)+H2O(g) Express your answer as a balanced chemical equation. Identify all of the phases in your answer.

2C3H6(g)+9O2(g)→6CO2(g)+6H2O(g)

Number of O atoms in 8.25×10−3 mol Al(NO3)3.

4.47×1022

2C8H18(l)+25O2(g)→16CO2(g)+18H2O(g) How many grams of O2 are needed to burn 14.0 g of C8H18

49.0

C6H6+Br2→C6H5Br+HBr What is the theoretical yield of bromobenzene in this reaction when 33.0 g of benzene reacts with 71.5 g of bromine

66.3

Nicotine, a component of tobacco, is composed of C, H, and N. A 7.875-mg sample of nicotine was combusted, producing 21.363 mg of CO2 and 6.125 mg of H2O. What is the empirical formula for nicotine? If nicotine has a molar mass of 160±5g/mol, what is its molecular formula?

C5H7N C10H14N2

empirical and molecular formulas

C5H8O4NNa,C5H8O4NNa

NH4NO3(s)→N2O(g)+H2O(l) Express your answer as a balanced chemical equation. Identify all of the phases in your answer.

NH4NO3(s)→N2O(g)+2H2O(l)

2NaOH(s)+CO2(g)→Na2CO3(s)+H2O(l) Which reagent is the limiting reactant when 1.86 mol NaOH and 1.00 mol CO2 are allowed to react?

NaOH

4NH3(g)+5O2(g)→4NO(g)+6H2O(g) In a certain experiment, 2.10 g of NH3 reacts with 3.85 g of O2. what is the limiting reactant

O2

When a compound containing C, H, and O is completely combusted in air, what reactant besides the hydrocarbon is involved in the reaction?

O2