WorksheetsMulti-Step Chemistry Problems Quiz - CAHS DL week 5
Total questions: 20
Worksheet time: 10mins
Why is it important to do multi-step calculations using one long factor-label table, rather than several separate calculations? (Choose the BEST answer.)
Because that's what our teachers told us to do.
There's no other way to do the math correctly.
It makes the math easier to read.
It's the best way to keep track of the units that are cancelled in the steps.
What is a good way to keep track of what to do next during a multi-step conversion problem?
Use a conversion map such as the "Mole Town" map.
Memorize the formulas and constants for every type of Chemistry problem.
The factor-label table keeps track for you, so you don't need anything else.
Look up the solution on Google.
What is the conversion factor between mass of a substance in grams and number of moles of the substance in that sample?
Ideal Gas Law
Molarity
Molar Mass
Avogadro's Number
What is the conversion factor between number of moles of substance and number of molecules of the substance?
Ideal Gas Law
Molarity
Molar Mass
Avogadro's Number
Which of the following would you use to determine the number of moles in a sample of gas with a known volume, temperature and pressure?
Ideal Gas Law
Molarity
Molar Mass
Avogadro's Number
When converting between units, it could be said that "Everything runs though ___________." Which unit best fills the blank? (Meaning that all the other units can be converted to that unit in one step.)
grams
moles
liters
particles
To convert between amount of reactant and amount of product produced in a chemical reaction, the amount of starting substance must be converted to what unit?
grams
atoms
particles
moles
When converting between amount of reactant and amount of product produced in a chemical reaction, the step to change from the starting substance into a different substance requires what conversion factor? (Hint: This conversion factor connects two different "Mole Towns".)
Molar Mass
Molarity
Mole Ratio
Molar Volume
Where do you find the mole ratio conversion factor for problems involving a chemical reaction?
The coefficients in the balanced chemical equation.
The subscripts in the correct chemical formulas.
The small number under the symbols on the periodic table.
It is determined by experimentation.
Which of the following conversion factors is a constant, meaning it is always the same value, no matter what substance is being converted?
Molar Mass
Molarity
Avogadro's Number
Mole Ratio
Which of the following conversions requires you to use subscripts from the chemical formula of a substance as part of the conversion factor?
grams to moles
mL to L
moles of A to moles of B
molecules to atoms
How many steps are required to convert between grams of solid A and liters of gas B at STP during a chemical reaction?
5
4
3
2
Why is it important to understand Chemistry nomenclature (names to formulas and vice-versa) when completing multi-step Chemistry problems?
Subscripts in formulas provide conversions between molecules and atoms.
Without correct formulas, you will not be able to correctly balance the chemical equation to obtain the mole ratio conversion factors.
Both answers are correct.
Neither answer is correct.
Consider the model reaction A+B → C+D
If you are given starting grams of both reactants A and B, why must you first determine which reactant is limiting before solving for grams of product C that can be produced?
Because there is a large amount of variation in chemical reactions.
Because the amount of product that can be produced is limited by the reactant that will run out first.
Because the highest amount of product is always correct.
Because you have to use the same amount of both reactants in order for the reaction to work.
When using the Ideal Gas Law (PV = nRT) to find the number of moles of gas in a multi-step problem, which units MUST be used for T?
atm
kPa
oC
K
N2(g) + H2(g) → NH3(g)
You are given the equation above and asked to solve for the volume of ammonia that can be produced at STP using 150.0 mL of nitrogen gas and 150.0 mL of hydrogen gas. What is the FIRST step you need to take?
Determine the limiting reactant.
Find the molar mass of ammonia.
Convert mL of the reactants to grams.
Balance the chemical equation.
You are given a problem that says "A 250.0-g sample of Mg is dropped into an excess of 2.0 M HCl solution. Calculate the volume of hydrogen gas produced at STP."
What should be your first step?
Determine the limiting reactant.
Balance the chemical equation.
Predict the products of the chemical reaction.
Convert grams of Mg to moles.
You are given a problem that says "A 250.0-g sample of Mg is dropped into an excess of 2.0 M HCl solution. Calculate the volume of hydrogen gas produced at STP."
You correctly predict the products as the first step then balance it as step 2 to give you: 2HCl(aq) +1Mg(s) → 1MgCl2(aq) + 1H2(g)
Why did you write the formulas as MgCl2 and H2 when it would have been easier to balance as MgCl + H ?
Because chlorine and hydrogen are always diatomic, even in compounds.
Because ionic compounds must have a net charge of zero and hydrogen as an element by itself is always diatomic.
Because ionic compounds must have a net charge of zero, and both products are ionic compounds.
Because I knew I had to change something.
You are given a problem that says"25.0 mL of 6.0 M HCl reacts with an excess of magnesium. Calculate the volume of hydrogen gas produced at STP."
You correctly predict the products as the first step then balance it as step 2 to give you: 2HCl(aq) +1Mg(s) → 1MgCl2(aq) + 1H2(g)
How many steps will be in your factor-label table to solve this problem?
8
6
4
2
You are given a problem that states "How much energy is produced from the combustion of 100.0 g of C4H10? (ΔH of C4H10 = -2876 kJ/mol)" How many steps will you need in your factor-label table?
8
6
4
2
