chemical reactions

Question 1

What is a chemical reaction?

Answer 1

It is when 2 or more elements combine to make a new product.

Question 2

What is a word equation?

Answer 2

A word equation shows the names of each substance in a reaction.

Question 3

What is a balanced equation?

Answer 3

A balanced equation gives more information about the reaction because it includes the symbols of the things involved.

Question 4

How do you write balanced equation?

Answer 4

You replace the name of each substance with its symbol or formula and use numbers to balance the equation.

Question 5

Is this a balanced equation Cu + O2 → CuO?

Answer 5

Cu + O2 → CuO is not a balanced equation because there is 2 oxygen on one side and only one on the other so it is not balanced. 2Cu + O2 → 2CuO this is a balanced equation.

Question 6

What is a Combustion reactions?

Answer 6

Combustion reactions is another name for burning.

Question 7

What do non metals react with to produce non metal oxide?

Answer 7

They react with oxygen to make non metal oxide

Question 8

what is an exothermic reaction?

Answer 8

Exothermic reaction is when energy is given out to the surroundings. It is when it gets hotter.

Question 9

What is an endothermic reaction?

Answer 9

An endothermic reaction is when energy is taken from the surroundings so the temperature falls.

Question 10

What is thermal decomposition?

Answer 10

Thermal decomposition is when Some compounds break down when heated, forming two or more products from one reactant.

Question 11

What is thermal decomposition an example of?

Answer 11

Thermal decomposition is an example of an endothermic reaction.

Question 12

What is a catalyst substance?

Answer 12

A catalyst is a substance that speeds up reactions

Question 13

What is a bond?

Answer 13

The chemical link that holds molecules together.

Question 14

What is a product?

Answer 14

A substance formed in a chemical reaction.

Question 15

Is everything made from an atom?

Answer 15

Yes.Even us!

Question 16

How many atoms are in the world?

Answer 16

There are over 100 different atoms in the world and these are called elements.

Question 17

What is an element?

Answer 17

something that only contains one atom type.

Question 18

How are chemical symbols written?

Answer 18

Every chemical symbol starts with a capital letter, with the second or third letters written in lower case.

Question 19

What does the chemical Li stand for?

Answer 19

Lithium.

Question 20

Are the chemical symbols the same all over the world?

Answer 20

Yes that is why some are wired like W stands for tungsten.

Question 21

The horizontal rows in the periodic table are called?

Answer 21

Periods.

Question 22

The vertical columns in the periodic table are called?

Answer 22

Groups.

Question 23

Are elements in the same group similar to each other?

Answer 23

Yes.

Question 24

Are the non metals on the left?

Answer 24

No they are on the left and the metals are on the right.

Question 25

Is hydrogen a non metal?

Answer 25

Yes but is is often put in the middle of the table.

Question 26

Are most elements metal or non-metal?

Answer 26

Most elements are metal.

Question 27

Are atoms the building blocks of everything?

Answer 27

Yes.

Question 28

Will you only ever see elements in the periodic table?

Answer 28

Yes no compounds.