Answer:
The average thermal conductivity of the material at this temperature range is 3*10^(-9) W/mK.
Explanation:
The heat flow through this area of the metal panel can be expressed as:
being A the surface area, k the thermal conductivity, T2 and T1 the temperatures in each side and Y the thickness of the metal panel.
We have to rearrange the equation to clear k:
The average thermal conductivity of the material at this temperature range is 3*10^(-9) W/mK.
Answer:
group 2
Explanation:
because they are the only alkalines earth metals on the periodic table
Answer:
2-naphtol is a weak acid and benzoic acid is a stronger acid. NaHCO3 is a weak base, that will only react with a strong acid like benzoic acid. 2-napthol is not soluble in sodium bicarbonate.
Explanation:
2-naphtol is a phenol. Phenol is made of a benzene attached to an OH group. So, it is a (big) organic molecule, and a little non-polar group. The conjugated (or non-localised) electrons in the benzene ring pull electrons away from the OH group. It makes it harder for the oxygen to steal the hydrogen's electrons and become O-.
A phenol is acidic in nature because of this H+ releasing. This will result in forming a phenoxide.
Benzoic acid is a carboxylic acid and is more acidic than a phenol. Since it's acid it will also release H+ ion, in this case to form carboxylate which is more stable than phenoxide. The phenoxide is resonance stabilised.
The negative charge , in carboxylate, is delecoalised on the negatively charged O atom what makes it more stable than phenoxide. Compared to carboxylic acid. ( or benzoic acid) phenol ( or 2-naphtol) is a weak acid.
NaHCO3 is a weak base and will only react with a strong acid like carboxylic acid. A naphtol is not strong enough to react with the weak base NaHCO3.
This means 2-naphtol is a weak acid and benzoic acid is a stronger acid. NaHCO3 is a weak base, that will only react with a strong acid like benzoic acid. 2-napthol is not soluble in sodium bicarbonate.