Home Chapter 3: Stoichiometry: Calculations with Chemical Formulas and Equations Quiz 1

# Quiz 1

This activity contains 12 questions.

Suppose you are setting up a reaction that requires an iodide salt and are planning to use sodium iodide. However, at the last minute you find that you are out of sodium iodide, so you must use potassium iodide instead. Will you need to weigh out more, less, or the same mass of potassium iodide in order to get the same number of moles of iodide ions?

 less same more

## Balance the following equation and indicate whether it is a combustion, combination, or decomposition reaction: Li + N2 Li3N

 Li + N2 3Li3N, decomposition 6Li + N2 2Li3N, combination reaction Li + N2 3Li3N, combination 6Li + N2 2Li3N, decomposition reaction 6Li + N2 2Li3N, combustion

## Balance the following equation: Mg3N2 + H2O Mg(OH)2 + NH3

 Mg3N2 + 2H2O Mg(OH)2 + NH3 Mg3N2 + 6H2O 3Mg(OH)2 + NH3 Mg3N2 + 3H2O 3Mg(OH)2 + 2NH3 Mg3N2 + 6H2O 3Mg(OH)2 + 2NH3

## Calculate the number of molecules in a tablespoon of table sugar, C12H22O11, weighing 10.5 g.

 2.22 x 1023 6.32 x 1024 6.02 x 1023 3.01 x 1023 1.85 x 1022

## Calculate the number of moles of water present in a 10.0-kg sample.

 55.5 mol none of these 1.80 x 102 mol 555 mol 1.80 x 105 mol

## Convert the following to a balanced chemical reaction: Gaseous hydrogen reacts with carbon monoxide to form methanol, CH3OH.

 H2 + CO CH3OH 4H + CO CH3OH 2H2 + CO CH3OH 2H2 + CO2 CH3OH

## How many F- ions are present in 2.50 mol of BaF2?

 8.31 x 10-24 1.51 x 1024 2.50 3.01 x 1024 5.00

## Potassium sulfate contains 44.9 percent potassium by mass. In a 50.0-g sample of potassium sulfate, the number of moles of potassium is

 0.574 mol. 1.74 mol. 0.287 mol. 1.28 mol. 2.00 mol.

## The reaction C7H8 + 3HNO3 ---> C7H5N3O6 + 3H2O can be used to make TNT. How many grams of HNO3 are required to react with 10.0 g of C7H8?

 6.81 g 30.0 g 10.1 g 20.5 g 2.28 g

## What is the formula weight of (NH4)2SO4?

 116 amu 100 amu 132 amu 118 amu

What mass of silver chloride can be made from the reaction of 4.22 g of silver nitrate with 7.73 g of aluminum chloride? (Be sure to balance the reaction.)

AgNO3 + AlCl3 Al(NO3)3 + AgCl

 12.7 g 3.56 g 24.9 g 10.7 g

## Write the balanced equation for the reaction that occurs when solid potassium nitrate is heated and decomposes to form solid potassium nitrite and oxygen gas.

 KNO3(s) KNO2(s) + (1/2)O2(g) 2KNO3 2KNO2 + O2 2KNO4(s) 2KNO3(s) + O2(g) 2KNO3(s) 2KNO2(s) + O2( g)