Lecture 5

Question 1

What is the maximum charge that Na has when ionized?

Answer 1

1+

Question 2

Li, Be, Na and Mg have how many valence electrons?

Answer 2

Li and Na have 1 valence electrons. Be and Mg have 2 valance electrons.

Question 3

What number of bonds does Li have?

Answer 3

Li has 1 bond.

Question 4

How many bonds does Na have?

Answer 4

Na has 1 bond.

Question 5

How many bonds does Be and Mg have?

Answer 5

Be and Mg have 2 bonds.

Question 6

Boron and Carbon only form what type of bonds?

Answer 6

Boron and Carbon only form covalent bonds.

Question 7

How many valance electrons does O have?

Answer 7

O has 6 valence electrons.

Question 8

Number of valence electrons for F?

Answer 8

F has 7 valence electrons.

Question 9

Alcohol must be within what percent of label declaration according to the VQA?

Answer 9

Alcohol tested by VQA must be within 1% of label declaration.

Question 10

Name 2 ways to determine alcohol.

Answer 10

1. Ebulliometer 2. Cash Still

Question 11

Benefits and Disadvantages for Ebulliometry to test for alcohol…

Answer 11

Benefits: quick and easy
Disadavantages: not for offical records or audits (i.e. VQA) and results are accurate to 0.5% difference.

Question 12

Describe how Ebulliometry works to measure alcohol

Answer 12

Ebulliometry uses the difference in boiling temp between distilled water and the wine to determine alcohol.

Question 13

How does the presence of sugar in wine affect Ebulliometry?

Answer 13

Roault’s Law: sugar affects the boiling point of the wine by raising the boiling point and isn’t accurate above 2% sugar content.

Question 14

Why are sulfites important to a winemaker?

Answer 14

a “winemakers insurance policy” against oxidation and microbial spoilage) (acts as a preservative: antioxident against oxidation and antimicrobial) It also binds to aldehydes which prevents reactions.

Question 15

What is the Atomic Number of Sulfur?

Answer 15

Atomic Number of Sulfur is 16

Question 16

How many protons does Sulfur have?

Answer 16

16

Question 17

How many electrons does Sulfur have?

Answer 17

16

Question 18

What is the atomic mass of Sulfur?

Answer 18

32 is the Atomic Mass of Sulfur

Question 19

How many neutrons does Sulfur have?

Answer 19

Atomic Mass - Proton #
=32 - 16
=16

Sulfur has 16 neutrons.

Question 20

What is Sulfur Dioxide (SO2)?

Answer 20

Sulfure with 2 Oxygens (DI-oxide)

Question 21

What happens when SO2 is in water?

Answer 21

In water, SO2 reacts and can be also called H2SO3

Question 22

When does Sulfurous Acid (H2SO3) form?

Answer 22

Sulfurous Acid (H2SO3) forms when SO2 is fully protonated in acidic aqueous solution (SO2 + H2O –> H2SO3)

Question 23

Which form of Sulfur is the most important in winemaking?

Answer 23

Sulfurous Acid (H2SO3) is the most important form of Sulfur in winemaking because:
-provides anti-microbial protection
-strongest antioxidant in this form reacting w/ H2O2 and aldehydes

Question 24

In which form is Sulfur most abundant?

Answer 24

Bisulfite (HSO3-) is the most abundant form of Sulfur.

Question 25

Describe Bisulfite Ion

Answer 25

-most abundant form of sulfur
-has some antioxidant properties
-binds to anthocyanins (grape skin pigments) masking colour

Question 26

Which form of sulfite is the least abundant at wine pH?

Answer 26

Sulfite (So32-) is the least abundant at wine pH. It is a strong antioxident that reacts quickly w oxygen.

Question 27

Which antimicrobial has some resistance to SO2?

Answer 27

Sacchromyces have some resistance to SO2.

Question 28

What is ppm?

Answer 28

Parts per Million = ppm
1/1,000,000 = 1 pppm

Question 29

The molecular SO2 should be at which ppm for microbial protection?

Answer 29

For microbial protection, the molecular SO2 should be 0.5-0.8ppm.

Question 30

Molecular SO2 is highly dependent on what?

Answer 30

Molecular SO2 is highly dependent on pH

Question 31

What is the FSO2 limit for bottled wine?

Answer 31

The FSO2 limit for bottled table wine is 50ppm.

Question 32

Where does the SO2 in the wine come from?

Answer 32

Yeast metabolism naturally produces yeast (10-3-ppm) and you can add KMS (Potassium metabisultite) to the wine (burning sulfur strips or pucks)

Question 33

What is the MW of SO2?

Answer 33

SO2 has a MW = 64.07 g/mol

Question 34

How many mol of solfite is given when K2S2O5 (KMS) is dissolved in an aqueous solution.

Answer 34

Each K2S2O5 (KMS) gives 2 mol of sulfite when dissolved in an aqueous solution. K2S2O5 (Potassium Metabisulfite) has MW = 222.34/mol

Question 35

What is the formula to calculate KMS (K2S2O5, Potassium Metabisulfite) required in the winemaking process?

Answer 35

g KMS = ppm S02/1000 X Volume of wine(L)/ 0.576

Question 36

Should you add more or less FSO2 if your grapes are “dirty”

Answer 36

Add more, add some extra

Question 37

How much FSO2 do you need?

Answer 37

During Grape Receival: Add 0-60ppm to the red must or white juice. At the end of fermentation: (when v. little FSO2 is present) you should add enough SO2 to reach between 0.5-0.8ppm molecular SO2

Question 38

According to VQA Ontario, what are the SO2 (Sulfur Dioxide) limits for wines w/less than 35g/L RS? (Non-dessert wines)

Answer 38

Free SO2: 50ppm
Bound SO2: 250ppm
Total = 400ppm

(For organic wines the total SO2 limit is 100ppm)

Question 39

According to VQA Ontario, what are the SO2 (Sulfur Dioxide) limits for wines w/more than 35g/L RS? (Dessert wines)

Answer 39

Free SO2: 70
Bound SO2: 330
Total SO2 = 400

Question 40

Name 2 Methods to test FSO2

Answer 40

Ripper Method and Aspirational Method

Question 41

What is the Oxidation State?

Answer 41

How many charges an atom holds (i.e. “Iron can exist in Fe2+ and Fe3+ oxidation state”) HINT: LEO GRE (Loose Electrons Oxidation - Gain Electrons Reduction)