Urea Formaldehyde Foam Insulation is the thermal insulation material that is no longer used because of formaldehyde gas emission
Urea Formaldehyde Foam Insulation is mixture of urea formaldehyde resin, foaming acid agent, and a propellant used in the 1970s for insulating purposes.
It was specifically designed to insulate the areas of the building that were hard to access. Unlike regular process, it was sprayed into the walls by using holes.
It is no longer used because it caused a raise in the formaldehyde gas in the residence. This gas caused irritations to the people living in the building. Residents started to report health issues like respiratory problems, and eyes, nose, throat irritation.
If you need to learn about the formaldehyde gas, click here.
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Let's say say there are n1 mols of helium in the first balloon and n2 mols of nitrogen in the second one, which are equivalent to m1 grams of helium and m2 grams of nitrogen.
The molar mass of hydrogen is thus M1=m1/n1, same for nitrogen M2=m2/n2 hence the ratio of their masses is m1/m2=(M1n1)/(M2n2). Since both gases are rather similar, we can assume that n1~n2 hence m1/m2=M1/M2
Answer:
energy goes into the chemical and cool downs the surrounding area.
Definitely definite mass because liquids can take on any shape and can have different volumes.
