T K = ºC + 273
T = 18 + 273
T = 291 K
hope this helps!
Explanation:
A chemical change results from a chemical reaction, while a physical change is when matter changes forms but not chemical identity. Examples of chemical changes are burning, cooking, rusting, and rotting. Examples of physical changes are boiling, melting, freezing, and shredding.
To understand why cooking is a chemical change, you should first understand what is a chemical change. Basically, all changes in this world can be classified as either physical changes or chemical changes. The difference is that chemical changes bring about new substances while physical changes don’t. Take the example of baking: when you bake a cake, the most immediately observable change is that it expands. This is because the baking soda in it has undergone a chemical change under heat to release carbon dioxide. Notice there is no carbon dioxide in the cake before we bake it. That is what I mean by bringing about new substances.
So why is cooking a chemical change? Because almost all cooking methods involving the rise of temperature (which is basically to say, all cooking methods) involve chemical changes. Once under heat, the antioxidants omnipresent in vegetables will get oxidized and the proteins in meats will get denatured. Among other things, the former process will mostly result in the change of color of the vegetables, and the latter the stiffening of the meats
The answer is C: How long does it take distilled water to evaporate from a 5” diameter container?
Here we have to get the temperature and pressure at which helium gas mostly behaves as ideal gas.
Helium (He) behave most like an ideal gas upto 24K temperature and 0 atm pressure.
The deviation of a real gas to ideal gas occurs at high temperature and low pressure.
The deviation of ideal gas to real gas occurs on taking into account the van der waals' force of attraction between the gas molecules. Now, the van der waals' interaction depends upon the polarisibility of the gas molecule.
As helium (He) is non-polarisable and very small (atomic number 2) it mostly behaves as ideal gas upto 24K temperature and 0 atm pressure.
Although the deviation from the ideal gas behavior to real gas is not so prominent at little high temperature also. Upto 50K it mostly behaves like an ideal gas.
