Grade 10 Chemistry Revision - Organic Chemistry and Environment

Comprehensive practice flashcards covering organic chemistry reactions, homologous series, polymerization, and environmental chemistry based on the lecture notes.

Why does the process of alcoholic fermentation stop after some time?

The yeast gets destroyed by the alcohol produced.

Define the term 'isomers' based on the but-1-ene and but-2-ene example.

Isomers have the same molecular formula ($C_4H_{10}O$ in the transcript's example) but different structural formulas or a different arrangement within the carbon chain.

What is cracking and what would be the original alkane if it produced one mole of hexane ($C_6H_{14}$) and two moles of ethene ($C_2H_4$)?

Cracking is the process of breaking down long chain saturated hydrocarbons into smaller, more useful molecules. The original alkane in this case is Decane, $C_{10}H_{22}$.

Describe the colour change when ethene is bubbled through aqueous bromine and explain why.

The colour changes from orange to colourless because alkenes are unsaturated and undergo an addition reaction with bromine.

If the degree is decreased from 40°C to 30°C what’s the effect on ethanol production by yeast industrial fermentation

personal yield decreases because yeast enzymes of the denatured

What happens when a mixture of methane and chlorine is exposed to UV light?

It undergoes a substitution reaction.

How does increasing the temperature of a glucose solution from $30^\circ C$ to $40^\circ C$ affect industrial fermentation?

The ethanol yield decreases because the yeast enzymes are denatured at the higher temperature.

What is the result of heating methanol and ethanoic acid with concentrated sulfuric acid?

An ester is formed, which has a fruity smell and an ester functional group.

What is the common linkage in proteins and synthetic polymers like nylon, and how do they differ?

They both have an amide linkage. Proteins are made from a variety of different amino acid monomers, whereas synthetic polymers like nylon consist of only one or two repeating units.

What type of polymerization takes place in PLA (polylactic acid) and why?

Condensation polymerization, because the presence of the ester linkage indicates that water or a small molecule was removed during the bonding of the monomers.

List two reasons why the rate of fermentation decreases over time.

1. Glucose is being used up, leaving fewer molecules to react. 2. The concentration of ethanol increases to a point where it becomes toxic and yeast is destroyed.

What are the percentages of nitrogen, oxygen, and argon in clean dry air?

The transcript identifies these as the main components of clean dry air, specifically naming Nitrogen, Oxygen, and Argon (and Carbon dioxide).

Explain how nitrogen dioxide ($NO_2$) is formed in car engines and state one adverse effect.

At high temperatures, nitrogen and oxygen from the air combine ($N_2 + O_2 \rightarrow 2NO_2$). An adverse effect is that it causes acid rain or respiratory problems.

Identify two common gaseous pollutants in air and how they are produced.

Carbon monoxide: produced by the incomplete combustion of carbon-containing fuels. Sulfur dioxide: produced by the combustion of fossil fuels that contain sulfur impurities.

How do carbon dioxide and methane contribute to global warming?

They emit the thermal energy they have absorbed back to the earth.