Exam 3: Composition of Substances and Solutions

A 0.125 g sample of unknown hydrocarbon is prepared for combustion analysis. After the hydrocarbon undergoes complete combustion, 0.4225 g of CO₂ and 0.0865 g of H₂O are produced. What is the empirical formula of the unknown? Paired item 1)

A 5.91 g unknown sample analyzed by elemental analysis revealed a composition of 37.51 %

Which of the following 85.0 g samples contain the greatest number of atoms?

How many moles contain 6.022 x 10²³ lithium atoms?

When a salt is dissolved in water, it is represented by the following notation in a chemical reaction?

Which of the following is a method used to allow scientists to determine an empirical formula and identify an organic compound by combusting a sample and the resulting combustion products are quantitatively analyzed?

Which of the following is an experimental technique used to determine the mass percent of elements found in a compound?

A 21.8 g sample of water contains how many water molecules?

How would you prepare a 1 M solution of sodium hydroxide?

An unknown hydrocarbon compound was analyzed for hydrogen by elemental analysis and results show that it contains 15.88 % H. What is the empirical formula?

How many grams are in 2.05 x 10²³ molecules of dinitrogen pentoxide?

How many atoms are in 1 mole of calcium?

How many grams of Hydrogen are present in three moles of Hydrogen?

Which of the following 49.5 g samples contain the fewest number of atoms? Paired item 1)

A sample has a molar mass of 143 g/mol, identify the sample.

How many moles are in 11.0 g of silver metal?

An experiment requires 15.0 mL of a 0.100 M solution of HCl. If you have a 12.0 M HCl stock solution in the laboratory, how would you prepare enough 0.1 M solution to run at least 3 experiments?

What is the total number of atoms contained in 2.11 moles of nickel?

How would you prepare a 0.5 M solution of sodium hydroxide? Paired item 1)

How many atoms are in 1.00 mole of Au? Paired item 1)