Answer:
If you contact water with a gas at a certain temperature and (partial) pressure, the concentration of the gas in the water will reach an equilibrium ('saturation') according to Henry's law.
Explanation:
This means: if you increase the pressure (e.g. by keeping the vial closed), the CO2 concentration will increase. So it simply depends what concentration you need for your assay: 'CO2-saturated' water at low pressure or 'CO2-saturated' water at high pressure.
The heat transfer just occurred is mainly conduction.
Conduction happens when two objects are in contact with each other. In the hotter object, the molecules and/or free electrons have a higher kinetic energy, thus they'll travel and collide into other molecules, resulting in spreading the energy to the other object.
The heat transfer happens until thermal equilibrium, where both objects have the same temperature and their molecules have the same kinetic energy rate.
In addition, radiation is also happening since everything that has a higher temperature than the environment is a net emitter. They release electromagnetic waves that turn out to be radiation. These occur even without the presence of air.
Answer:
Element 2
Explanation:
If we look at the model stated for element 1, it is clear that element 1 must be a noble gas. It has eight electrons in its outermost shell this implies that it has already attained a complete octet of electrons and is reluctant towards chemical reaction.
The second element belongs to group 16 since it has six electrons on its outermost shell. It is certainly more reactive than element 1 which is a noble gas.