Gr.10 T4 Chemistry

Question 1

What is the difference between ionic compounds and acids dissolving in water?

Answer 1

Ionic compounds dissociate in water

Acids ionise in water

Question 2

What is the force between ions and water molecules called?

Answer 2

Ion-dipole force

Question 3

Name the two forces in molecules (you know what I mean😉)

Answer 3

Intermolecular forces and electrostatic forces

Question 4

What is dissolving?

Answer 4

The process of a solid ionic crystal breaking down into its ions

Question 5

What is hydration?

Answer 5

The process where water molecules now surround the positive and negative ions of a once ionic compound

Question 6

What is an electrolyte?

Answer 6

A liquid solution with positive and negative ions that are free to move. The ions carry charge, making the liquid able to conduct electricity.

Question 7

What does a solution consist of?

Answer 7

Solute (minority) in a solvent (majority)

Question 8

What solutes does hard water have dissolved in it?

Answer 8

Calcium and magnesium ions

Question 9

What is a precipitation reaction?

Answer 9

When a combination of ions forms an insoluble salt

Question 10

What colour is Al(OH) ?

3

Answer 10

White

Question 11

What colour is Cu(OH) ?

2

Answer 11

Blue

Question 12

What colour is Fe OH

2

Answer 12

Green

Question 13

What colour is Pb I

2

Answer 13

Yellow

Question 14

AgNO (aq) is added to an unknown. 
         3
A white precipitate forms that is 
insoluble in an acid. 
What is the unknown?

Answer 14

It contains chloride ions.

Question 15

AgNO (aq) is added to an
         3
unknown. A cream precipitate forms that is 
insoluble in an acid. 
What is in the unknown?

Answer 15

It contains bromide ions

Question 16

AgNO (aq) is added to an
3
unknown. A yellow precipitate forms that is insoluble in an acid. What is in the unknown?

Answer 16

It contains iodide ions

Question 17

Ba(NO ) (aq) is added to
3 2
an unknown. A white precipitate forms that is insoluble in an acid. What is in the unknown?

Answer 17

It contains sulphate

Question 18

Ba(NO ) (aq) is added to
3 2
an unknown. A white precipitate forms that is soluble in an acid and releases a gas. What is in the unknown?

Answer 18

It contains carbonate ions

Question 19

Name the 4 types of chemical reactions and briefly describe them.

Answer 19

Precipitation: insoluble salt
Gas-forming reaction: gas comes off
Acid-base reaction: transfer of protons
Redox reaction: transfer of electrons

Question 20

What precipitate does an unknown with chloride ions form when added to sliver nitrate solution?

Answer 20

A white precipitate that is insoluble in acid.

Question 21

What precipitate does an unknown with bromide ions form when added to sliver nitrate solution?

Answer 21

A cream precipitate that is insoluble in acid.

Question 22

What precipitate does an unknown with iodide ions form when added to sliver nitrate solution?

Answer 22

A yellow precipitate that is insoluble in acid.

Question 23

What precipitate does an unknown with sulphate ions form when added to barium nitrate solution?

Answer 23

A white precipitate that is insoluble in acid.

Question 24

What precipitate does an unknown with carbonate ions form when added to barium nitrate solution?

Answer 24

A white precipitate that is soluble in acid.

The reaction also releases a gas

Question 25

Name 3 properties of acids

Answer 25

Have a sour taste. Cause colour changes in plant dyes. React with certain metals like zinc, magnesium and iron to produce hydrogen gas. React with carbonates and hydrogen carbonates to produce carbon dioxide gas. Aqueous solutions of acids conduct electricity.

Question 26

Name 3 properties of bases

Answer 26

Have a bitter taste Feel slippery Cause colour changes in plant dyes Aqueous solutions conduct electricity (called alkalis)

Question 27

What colour does Methyl orange go in an acid/ base?

Answer 27

Acid: orange Base: yellow

Question 28

What colour does Bromothymol blue go in an acid/ base?

Answer 28

Acid: yellow Base: blue

Question 29

What colour does litmus go in an acid/ base?

Answer 29

Acid: red Base: blue

Question 30

What colour does Phenolphthalein go in an acid/ base?

Answer 30

Acid: colourless Base: pink

Question 31

What are acids?

Answer 31

Ionise in water to produce H+ ions

Question 32

What are bases?

Answer 32

Ionise in water to produce OH- ions

Question 33

What is a pH?

Answer 33

A measure of the acidity of a substance.

Question 34

Acid+base=

Answer 34

Salt+water

Question 35

Acid+metal oxide=

Answer 35

Salt+water

Question 36

Acid+metal carbonate=

Answer 36

Salt+water+carbon dioxide

Question 37

Acid+metal=

Answer 37

Salt+hydrogen

Question 38

What is a redox reaction?

Answer 38

Involves electron transfer

Question 39

In redox reactions, what do oxidation and reduction refer to?

Answer 39

Oxidation: neutral atom forms positive ion(s) and electron(s). Reduction: positive ion(s) and electron(s) form a neutral atom

Question 40

What are the 3 types of redox reactions?

Answer 40

Hydrogen displacement Metal displacement Halogen displacement

Question 41

What is the relative atomic mass of an element?

Answer 41

A value that compares the mass of one atom of that element with the mass of one atom of carbon-12

Question 42

Is the relative molecular mass (M) of a molecule?

Answer 42

The sum of atomic masses of all atoms in that compound. It's compares mass of a formula unit with mass of a carbon – 12 atom

Question 43

What is an empirical formula?

Answer 43

The simplest mole ratio of the elements making up a compound

Question 44

What is a molecular formula?

Answer 44

It shows the actual number of atoms of each element present in a molecule

Question 45

What are hydrated salts?

Answer 45

Crystals with water molecules attached to them

Question 46

What is concentration?

Answer 46

The amount of solute present in a given quantity of solvent. (mol per litre)

Question 47

What is molarity/molar concentration?

Answer 47

The number of moles of solute in 1 L of solvent

Question 48

What is a standard solution?

Answer 48

A solution of which the concentration is known exactly

Question 49

What do you call a flask with an exact volume?

Answer 49

A volumetric flask

Question 50

What does STP stand for?

Answer 50

Standard temperature pressure