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

2nd 6w CAT

8th Grade Science 2nd Six Weeks CAT

QuestionAnswer
The subscripts in a formula provide information about… The number of atoms of each element present
Name a coefficient in this equation: MgSO4 + 2HCl yields MgCl2 + H2SO4 Coefficient: 2 before HCl
Which equation is balanced? CuO + 2HCl yields CuCl2 + H2O or 6CO2 + 6H2O yields C6H12O6 + 4O2 CuO + 2HCl yields CuCl2 + H2O with Cu-1 on each side, H-2 on each side, Cl -2 per side
Which of the equations is unbalanced? CuO + 2HCl yields CuCl2 + H2O or 6CO2 + 6H2O yields C6H12O6 + 4O2 6CO2 + 6H2O yields C6H12O6 + 4O2 with O – 18 on reactant side; 14 on product side
Which equation is balanced? 4 Fe + 6 Cl2 yields 4 FeCl3 or HCl + 2NaCO3 yields H2CO3 + 2NaCl 4 Fe + 6 Cl2 yields 4 FeCl3 with Fe -4 per side, Cl – 12 per side
Which of the equations is unbalanced? 4 Fe + 6 Cl2 yields 4 FeCl3 or HCl + 2NaCO3 yields H2CO3 + 2NaCl HCl + 2NaCO3 yields H2CO3 + 2NaCl with H–1 on reactant side and H-2 on product side; Cl-1 on reactant side and Cl-2 on product side;
Name the reactants in the equation: MgSO4 + 2HCl yields MgCl2 + H2SO4 Reactants: MgSO4 + 2HCl
Name the products in the equation: MgSO4 + 2HCl yields MgCl2 + H2SO4 Products: MgCl2 + H2SO4
What information do the subscripts in this chemical formula tell you about this substance? Cu(NO3)2 There is 1 atom of copper, 2 atoms of nitrogen, and 6 atoms of oxygen: Total atoms: 9 atoms
How many atoms of oxygen can be found in the reactants of this equation? 6CO2 + 6H2O yields C6H12O6 + 4O2 18
Which of the following is true about the law of conservation of mass? The mass of the reactants must always equal the mass of the products
What is the number of hydrogen, sulfur, and oxygen atoms in 5H2SO4? H:10, S:5, O:20
In the Law of Conservation of Mass, what happens to the atoms involved in a chemical reaction? Reactant atoms are rearranged to form new compounds called the products in a balanced equation.
If a chemical equation is balanced.. Mass is conserved and stays the same on both sides of the equation
Indications that a chemical reaction has occurred include: Production of a gas (bubbling or fizzing); Change in color (like rust on a nail); Production of heat or cold or light (energy exchange); Formation of a precipitate (solid forms in a liquid); Burning a substance (like coal)
How do you know if a chemical reaction has taken place? New substances are formed, like a solid, or precipitate, with different properties
New substances formed in a chemical reaction are shown… On the right side of the equation and are called products
Reactants in a chemical reaction are On the left side of the equation
Equation: Sb2S3 + 3Fe yields 3FeS +2 Sb Reactants: Sb2S3 + 3Fe Products: 3FeS +2 Sb
How many atoms are present on the reactant side of: Sb2S3 + 3Fe yields 3FeS +2 Sb Sb:2 + S:3 + Fe:3 = 8
How many atoms are present on the product side of: Sb2S3 + 3Fe yields 3FeS +2 Sb Fe atoms = coefficient 3 x subscript 1 = 3; S atoms = coefficient 3 x subscript 1 = 3; Sb atoms = coefficient 2 x subscript 1 = 2; Total: 8 atoms
A white solid produced in a chemical reaction is called a… precipitate
How many Elements are in the compound Mg(OH)2 3 Elements: Magnesium, Oxygen, and Hydrogen
How many elements are in the chemical formula O2 1 element
Number of Atoms in H2CO3 2H + 1C + 3O = 6 atoms in all
Number of Hydrogen atoms in 4HNO3 coefficient 4 x subscript 1 = 4 atoms of H
Balanced Equations have number of each atom in reactant = number of each atom in product
Balanced equations demonstrate the Law of Conservation of mass because the number of atoms in the reactants = the number of atoms in the products.
Example of Balanced equation: NH4NO2 yields N2 + 2H2O 2 atoms of N on each side; 4 atoms of H on each side; 2 atoms of O on each side
Example of Un-Balanced Equation: 4 atoms of H reacting on left, but… 2 atoms reacting on the left, but... NH4NO2 yields N2 + H2O: Only 2 atoms of H produced on right; Only 1 atom of O produced on right
Unbalanced equations violate… The Law of Conservation of Mass
When 2 unequal forces pull in opposite directions, how do you find the Net Force? The direction? Subtract the unbalanced forces to find the net force. Movement will be to the direction of the greater force.
When more than 2 unequal forces are involved, how do you find the Net Force? The direction? Combine like forces, then subtract the forces. If still unbalanced, movement will be toward the direction of the greater force.
In order to move an object, you must exert a force that is Stronger than the friction force
When objects bump, the larger one exerts greater force on the smaller
An object in motion, not subject to any force, will Continue in motion at a constant speed in a straight line
A speeding car that stops suddenly will cause passengers without seat belts to… Continue to move forward in a straight line, at first
If forces are balanced, Net Force is 0 Newtons
In football, a player with more mass (in Kg) and a player with less mass (in Kg) have a head-on collision. Result? The player with more mass will push the player with less mass backwards because he exerts greater force.
Several vehicles are moving along at the same speed. Which one can come to a complete stop First? The smallest vehicle can stop first because it has less mass.
To go forward in water, you push the water backward
When swimming, The action force: pushing on the water with hands and feet;
When swimming, the reaction force: the water pushing back on hands and feet;
When swimming, the reaction force: moves you forward
Opposing forces that push: two arrows pointing towards each other
To find the net force of opposing forces: Subtract!
Forces that move together: two arrows pointing in the same direction
To find the net force of forces that move together: Add!
If you push against a car with a force of 30 N and the car does not move, The car is pushing back on you with a force that is greater than 30 N
Created by: m9000038
 

 



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