Question

Question
1
Question
2
Question
3
A)
In order for a reaction to occur, which action must happen?
(1 point)
Molecules must divide at a high enough energy to break bonds.
Molecules must collide at a low enough energy to break bonds.
Molecules must divide at a low enough energy to break bonds.
Molecules must collide at a high enough energy to break bonds.
A)
Which phrase best describes
activation energy
?
(1 point)
the energy required to rearrange and switch individual molecules within two compounds
the energy given off when rearranging and switching individual molecules within two compounds
the minimum amount of energy required to form bonds and end a chemical reaction
the minimum amount of energy required to break bonds and start a chemical reaction
A)
Molecules are not reacting using current methods. Which change can encourage a reaction?
(1 point)
adding another chemical
adding heat
removing heat
speeding up the molecules by mixing
Question
4
Question
5
A)
When sodium (Na) and chlorine (Cl) are combined, a small amount of table salt is formed and abright yellow light and a lot of heat are given off. Does it take more energy to break the bonds of thereactants, or is more energy released when forming the bonds of the products? How do you know?
(1 point)
It takes more energy to break the bonds of the reactants because yellow light is given off, which indicates
energy was absorbed in the beginning.
More energy is released when forming the bonds of the products because a lot of heat is given off, which
indicates energy was released.
More energy is released when forming the bonds of the products because yellow light is given off, which
indicates energy was released.
It takes more energy to break the bonds of the reactants because a lot of heat is given off, which indicates
energy was absorbed in the beginning.
A)
When hydrogen burns in oxygen and forms water, which bonds are broken and which bonds areformed?
(1 point)
Two H–H bonds are broken, one O=O bond is broken, and two H–O bonds are formed.
Two H–H bonds are broken, one O=O bond is broken, and four H–O bonds are formed.
Two H–H bonds are broken, one O–O bond is broken, and four H–O bonds are formed.
One H–H bond is broken, one O–O bond is broken, and two H–O bonds are formed.

Answer 1

1) Molecules must collide at a high enough energy to break bonds.

2) Activation energy = the minimum amount of energy required to break bonds and start a chemical reaction.

3) Adding heat.

4) More energy is released when forming the bonds of the products because a lot of heat is given off, indicating an exothermic reaction.

5) Two H–H bonds are broken, one O=O bond is broken, and four H–O bonds are formed.