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Keep the bottle cold and in an upright position. If you drink the coke within a day or two, it will keep fresh and sparkling, and you should hardly notice the difference.

Tip: The more coke there is inside the bottle (and the less air), the less CO2 will escape from the coke and into the (closed) bottle while it is stored in the fridge (results from Henry's law). Pour over coke from a half-full bottle over to a smaller container (or into another half-full bottle of coke, to fill one single bottle), and you will save space and loose less sparkling gas.

enter image description here

Some theory

CO2 "evaporation" is a result of the gas trying to reach an equilibrium between what is solved in the liquid (coke) and what is in the air above (Henry's law).

Keep in mind:
  1. Less CO2 escapes if the temperature is kept low (CO2 is more 'soluble' in low temperature, and less will escape from the liquid)
  2. Less CO2 escapes if the bottle is kept upright (smaller surface area than when the bottle is laid down, so this will slow down the 'evaporation' process)
  3. Less CO2 escapes if the bottle is almost full (smaller 'air' volume to fill with CO2 escaping from the liquid)
Also remember:

The moment you have opened a bottle of coke, then non-sterile air from the surroundings mixes with the content inside the bottle. An opened container will only keep fresh (without growth of bacteria or fungus) for a limited number of time (a week or two).  

Keep the bottle cold and in an upright position. If you drink the coke within a day or two, it will keep fresh and sparkling, and you should hardly notice the difference.

Tip: The more coke there is inside the bottle (and the less air), the less CO2 will escape from the coke and into the (closed) bottle while it is stored in the fridge (results from Henry's law). Pour over coke from a half-full bottle over to a smaller container (or into another half-full bottle of coke, to fill one single bottle), and you will save space and loose less sparkling gas.

Some theory

CO2 "evaporation" is a result of the gas trying to reach an equilibrium between what is solved in the liquid (coke) and what is in the air above (Henry's law).

Keep in mind:
  1. Less CO2 escapes if the temperature is kept low (CO2 is more 'soluble' in low temperature, and less will escape from the liquid)
  2. Less CO2 escapes if the bottle is kept upright (smaller surface area than when the bottle is laid down, so this will slow down the 'evaporation' process)
  3. Less CO2 escapes if the bottle is almost full (smaller 'air' volume to fill with CO2 escaping from the liquid)
Also remember:

The moment you have opened a bottle of coke, then non-sterile air from the surroundings mixes with the content inside the bottle. An opened container will only keep fresh (without growth of bacteria or fungus) for a limited number of time (a week or two).  

Keep the bottle cold and in an upright position. If you drink the coke within a day or two, it will keep fresh and sparkling, and you should hardly notice the difference.

Tip: The more coke there is inside the bottle (and the less air), the less CO2 will escape from the coke and into the (closed) bottle while it is stored in the fridge (results from Henry's law). Pour over coke from a half-full bottle over to a smaller container (or into another half-full bottle of coke, to fill one single bottle), and you will save space and loose less sparkling gas.

enter image description here

Some theory

CO2 "evaporation" is a result of the gas trying to reach an equilibrium between what is solved in the liquid (coke) and what is in the air above (Henry's law).

Keep in mind:
  1. Less CO2 escapes if the temperature is kept low (CO2 is more 'soluble' in low temperature, and less will escape from the liquid)
  2. Less CO2 escapes if the bottle is kept upright (smaller surface area than when the bottle is laid down, so this will slow down the 'evaporation' process)
  3. Less CO2 escapes if the bottle is almost full (smaller 'air' volume to fill with CO2 escaping from the liquid)
Also remember:

The moment you have opened a bottle of coke, then non-sterile air from the surroundings mixes with the content inside the bottle. An opened container will only keep fresh (without growth of bacteria or fungus) for a limited number of time (a week or two).

2 improved tip
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Keep the bottle cold and in an upright position. If you drink the coke within a day or two, it will keep fresh and sparkling, and you should hardly notice the difference.

Tip: The more coke there is inside the bottle (and the less air), the less CO2 will escape from the coke and into the (closed) bottle while it is stored in the fridge (results from Henry's law). So if you have littlePour over coke left, you might want to pour itfrom a half-full bottle over to a smaller container (or into another half-full bottle of coke, to fill one single bottle), and you will save space and loose less sparkling gas.

Some theory

CO2 "evaporation" is a result of the gas trying to reach an equilibrium between what is solved in the liquid (coke) and what is in the air above (Henry's law).

Keep in mind:
  1. Less CO2 escapes if the temperature is kept low (CO2 is more 'soluble' in low temperature, and less will escape from the liquid)
  2. Less CO2 escapes if the bottle is kept upright (smaller surface area than when the bottle is laid down, so this will slow down the 'evaporation' process)
  3. Less CO2 escapes if the bottle is almost full (smaller 'air' volume to fill with CO2 escaping from the liquid)
Also remember:

The moment you have opened a bottle of coke, then non-sterile air from the surroundings mixes with the content inside the bottle. An opened container will only keep fresh (without growth of bacteria or fungus) for a limited number of time (a week or two).

Keep the bottle cold and in an upright position. If you drink the coke within a day or two, it will keep fresh and sparkling, and you should hardly notice the difference.

Tip: The more coke there is inside the bottle (and the less air), the less CO2 will escape from the coke and into the (closed) bottle while it is stored in the fridge (results from Henry's law). So if you have little coke left, you might want to pour it over to a smaller container.

Some theory

CO2 "evaporation" is a result of the gas trying to reach an equilibrium between what is solved in the liquid (coke) and what is in the air above (Henry's law).

Keep in mind:
  1. Less CO2 escapes if the temperature is kept low (CO2 is more 'soluble' in low temperature, and less will escape from the liquid)
  2. Less CO2 escapes if the bottle is kept upright (smaller surface area than when the bottle is laid down, so this will slow down the 'evaporation' process)
  3. Less CO2 escapes if the bottle is almost full (smaller 'air' volume to fill with CO2 escaping from the liquid)
Also remember:

The moment you have opened a bottle of coke, then non-sterile air from the surroundings mixes with the content inside the bottle. An opened container will only keep fresh (without growth of bacteria or fungus) for a limited number of time (a week or two).

Keep the bottle cold and in an upright position. If you drink the coke within a day or two, it will keep fresh and sparkling, and you should hardly notice the difference.

Tip: The more coke there is inside the bottle (and the less air), the less CO2 will escape from the coke and into the (closed) bottle while it is stored in the fridge (results from Henry's law). Pour over coke from a half-full bottle over to a smaller container (or into another half-full bottle of coke, to fill one single bottle), and you will save space and loose less sparkling gas.

Some theory

CO2 "evaporation" is a result of the gas trying to reach an equilibrium between what is solved in the liquid (coke) and what is in the air above (Henry's law).

Keep in mind:
  1. Less CO2 escapes if the temperature is kept low (CO2 is more 'soluble' in low temperature, and less will escape from the liquid)
  2. Less CO2 escapes if the bottle is kept upright (smaller surface area than when the bottle is laid down, so this will slow down the 'evaporation' process)
  3. Less CO2 escapes if the bottle is almost full (smaller 'air' volume to fill with CO2 escaping from the liquid)
Also remember:

The moment you have opened a bottle of coke, then non-sterile air from the surroundings mixes with the content inside the bottle. An opened container will only keep fresh (without growth of bacteria or fungus) for a limited number of time (a week or two).

1
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Keep the bottle cold and in an upright position. If you drink the coke within a day or two, it will keep fresh and sparkling, and you should hardly notice the difference.

Tip: The more coke there is inside the bottle (and the less air), the less CO2 will escape from the coke and into the (closed) bottle while it is stored in the fridge (results from Henry's law). So if you have little coke left, you might want to pour it over to a smaller container.

Some theory

CO2 "evaporation" is a result of the gas trying to reach an equilibrium between what is solved in the liquid (coke) and what is in the air above (Henry's law).

Keep in mind:
  1. Less CO2 escapes if the temperature is kept low (CO2 is more 'soluble' in low temperature, and less will escape from the liquid)
  2. Less CO2 escapes if the bottle is kept upright (smaller surface area than when the bottle is laid down, so this will slow down the 'evaporation' process)
  3. Less CO2 escapes if the bottle is almost full (smaller 'air' volume to fill with CO2 escaping from the liquid)
Also remember:

The moment you have opened a bottle of coke, then non-sterile air from the surroundings mixes with the content inside the bottle. An opened container will only keep fresh (without growth of bacteria or fungus) for a limited number of time (a week or two).