Chemistry stuff I can't seem to remember

Question 1

Describe the trends of group 17.

Answer 1

• Known as Halogens
• Highly reactive
• form DIATOMIC molecules (go around a paired atoms)

Question 2

Describe the trends of group 18.

Answer 2

• noble inert gases

- MONATOMIC (don’t go around as paired atoms)

Question 3

metal + HCl —>

Answer 3

Metal Chloride + Hydrogen gas

Question 4

element + Oxygen —>

Answer 4

Element Oxide

Question 5

Decomposition:

Answer 5

XY—> X+Y

Question 6

precipitate:

Answer 6

ions swap over

Question 7

Displacement

Answer 7

a single reactant breaks down into 2 or more products:

2KClO3 —> 2KCl+3O2

Question 8

Combination:

Answer 8

X+Y—>XY

Question 9

How does the activity series work?

Answer 9

If the solution is above the metal - no reaction

solution below metal - reaction

Question 10

How does Surface area effect the rate of reaction?

Answer 10

Larger surface area = more exposed atoms. This means more particles react at the same time, increasing reaction rate.

Question 11

How does agitation effect the rate of reaction?

Answer 11

Ensures reactants are kept in contact by removing build-up of products around reactants.

Question 12

How do Catalysts effect the rate of reaction?

Answer 12

Chemicals that speed up reactions.

• reduce amount of energy required to turn reactants into products.
• make it easier for reactant molecules to collide and form products