Chemistry unit extra cards

Question 1

What are the five clues of a chemical reaction?

Answer 1

1. odour produced
2. temperature change
3. colour change
4. bubble formation (gas is formed)
5. precipitate formed

Question 2

What is the difference between a molecular compound and an ionic compound?

Answer 2

Ionic compounds are made up of a non-metal and a metal, whereas molecular compounds are made up of only non-metal atoms.

Question 3

What is the difference between the bond of an ionic compound and that of a molecular compound?

Answer 3

In a ionic compound, the two elements have exchanged one or more electrons in order to both have full outer shells. In molecular compounds, the two atoms are sharing one or more electrons to have a full outer shell.

Question 4

What is an ion?

Answer 4

An ion is a charged atom or group of ions.

Question 5

How are ions formed?

Answer 5

Atoms become ions by gaining or losing electrons

Question 6

What are cations? How are they formed?

Answer 6

When METALS become ions by losing electrons, it means they have less electrons than protons. This means it has become positively charged, or a cation.

Question 7

What are anions? How are they formed?

Answer 7

NON-METAL atoms gain electrons and become negatively charged, meaning they have more electrons than protons. By gaining enough electrons to fill their valence shell,they become anions.

Question 8

What atoms don’t naturally form ions?

Answer 8

Noble inert gases, Boron, Carbon and Silicon

Question 9

How do you know if an ionic formula is correct?

Answer 9

If the charges cancel each other out

Question 10

What kind of charge attracts cations and anions to each other?

Answer 10

electrostatic charges

Question 11

How do you determine ionic formulas?

Answer 11

Cross the charges, then Greatest Common Factor/GCF (take the charge of one ion and make it the subscript of the other)

Question 12

What order do we write ions in for formulas?

Answer 12

Cation, then anion

Question 13

How can we tell if something is a polyatomic ion?

Answer 13

If there are 2 or more capital letters in the formula

Question 14

When do we put brackets around polyatomic ions?

Answer 14

If we are increasing the number of full polyatomic ions

Question 15

What is Sn? Cu? Fe?

Answer 15

Sn - tin, Cu - copper, Fe - iron

Question 16

How do we name ionic compounds? What if the anion is polyatomic?

Answer 16

Full name of the cation, then root of the anion with the added suffix ‘ide’. If the anion is polyatomic, leave it’s full name.

Question 17

What are the main multivalent ions? What are their charges?

Answer 17

Iron, tin and copper. Cu - 1+, 2+. Fe - 2+, 3+. Sn - 2+, 4+

Question 18

Do multivalent ion charges appear in their formulas?

Answer 18

We do not write the charges in formulas

Question 19

How do we write multivalent ions in compound names?

Answer 19

We write them first, then put their charges in brackets in roman numerals

Question 20

What has to be included in drawings of compounds?

Answer 20

Charges and electron transfers

Question 21

How do we write oxygen’s name as a single ion in a covalent compound?

Answer 21

monoxide

Question 22

How do we know if something is a molecular/covalent compound?

Answer 22

If it is entirely made up of non-metals, it is a covalent compound.

Question 23

What is a covalent/molecular compound? How is on formed?

Answer 23

Molecular compounds are composed of 2 or more different non-metals. They are formed when atoms share at least one pair of electrons, forming a covalent bond.

Question 24

Are molecular compounds neutral? Why or why not?

Answer 24

There is no transfer of electrons, so the atoms stay neutral and molecular compounds are therefore neutral.

Question 25

Where are the non-metals? The metals?

Answer 25

Right of the staircase and Hydrogen = non-metals. Left of the staircase = metals.

Question 26

What do we call the elements in the row farthest to the right in the periodic table?

Answer 26

Noble gases

Question 27

What do we call the elements in the row farthest to the left in the periodic table?

Answer 27

Alkali metals

Question 28

What do we call the elements in the row second farthest to the right in the periodic table?

Answer 28

Halogens

Question 29

What do we call the elements in the row second farthest to the left in the periodic table?

Answer 29

Alkali earth metals

Question 30

What is a neutralization reaction?

Answer 30

When an acid and a base react to form water (the combination of H+ and OH-) and a salt

Question 31

What is an electrolyte?

Answer 31

A liquid or gel that contains ions and can be decomposed by electrolysis

Question 32

Can pure water conduct electricity?

Answer 32

Pure water does not because it does not contain loose ions (H+ and OH- are fully bonded and do not separate).

Question 33

What happens to the pH when water is added to a strong base?

Answer 33

It’s pH will drop with dilution.

Question 34

Why are bases conductors in solution?

Answer 34

Bases have dissociation constants - a percentage of them will separate into charged ions, meaning they can conduct electricity.

Question 35

Why would a strong acid make a lightbulb light up more brightly than a weak acid is it is used as a conductor?

Answer 35

Stronger acids have higher dissociation constants, meaning a higher percentage of them would separate into ions, and they conduct electricity more efficiently.

Question 36

How much more concentrated is a solution with a pH of 14 compared to 10?

Answer 36

10 000 times less concentrated - 14-10 = 4; add four 0s to 1; less concentrated because it has a higher dissociation constant