Save
Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
focusNode
Didn't know it?
click below
 
Knew it?
click below
Don't know
Remaining cards (0)
Know
0:00
share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Chapter 4 (Part 1)

Stoichiometry: Calculating Chemical Quantities (Test 1)

QuestionAnswer
mole the SI unit for amount of substance; the quantity of a substance that contains as many molecules or formula units as there are atoms in exactly 12g of carbon-12
Mole is what kind of word? "number"
Mole relates to what? mass
What do you use to convert moles to grams or grams to moles? molar mass
molar mass the mass of 1 mol of a substance
What is the equation for molar mass? mass/# of moles
What kind of ratios does the mole concept provide? mol-to-mol ratios
Where can you get mol-to-mol ratios? a) from the subscripts of chemical formulas or b) from the coefficients of balanced equations
What should you do when balancing equations? 1. Save lone elements for last. 2. Underline as you go.
When a hydrocarbon or a compound containing only C, H, and O undergoes complete combustion in oxygen, what is formed? carbon dioxide and water.
hydrocarbon a compound containing only carbon and hydrogen
What is the formula for percent yield? (actual yield/theoretical yield) times 100%
What should you do for limiting reactant problems? 1. Write a balanced chemical equation. 2. Determine the theoretical yield for both reactants. 3. The smaller theoretical yield belongs to the limiting reactant; the larger theoretical yield belongs to the excess reactant.
What should you do to determine percent by mass? % of an element = (mass of element/total mass of compound) times 100%
What does a molecular formula show? the number of atoms of each element in a molecule
What does an empirical formula show? the smallest whole number mol-to-mol ratio of elements
What are two ways to solve empirical/molecular formula problems? 1. Given only percentages by mass, assume 100g of unknown. Multiply the decimal equivalents by 100 to determine the moles. 2. Given percentages by mass and molar mass of the compound, multiply the decimal equivalents to determine the moles.
In combustion analysis, what does all of the carbon in the unknown get converted to? carbon dioxide
In combustion analysis, what does all of the hydrogen in the unknown get converted to? water
How do you determine the molecular formula from the empirical formula given the molar mass of the compound? Divide the molar mass of the compound by the molar mass of the empirical formula. Multiply the subscripts of the empirical formula by the resulting number.
Created by: 2nenogirl
 

 



Voices

Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards