Cat urine. May sound weird, may get it wrong, but it's true. Your teacher'll freak out.
Heat is needed to change solid to liquid even to gas!
Answer:
On edge nuity, it is 79.
Explanation:
Please read the explanation.
Since u have no coefficients, this problem is super easy.
You just add your products, 115.5+69.91 = 185.41
Then add your reactants: 49.8+56.5= 106.3
Then subtract your reactants from your product and round to the nearest whole number.
106.3-185.41=79
It's really easy. Once u understand it, you can do any problem like this. If there is coefficients, just multiply the coefficient by the amount given to you in the problem.
Answer:
333.7g of antifreeze
Explanation:
Freezing point depression in a solvent (In this case, water) occurs by the addition of a solute. The law is:
ΔT = Kf × m × i
Where:
ΔT is change in temperature (0°C - -20°C = 20°C)
Kf is freezing point depression constant (1.86°C / m)
m is molality of solution (moles solute / 0.5 kg solvent -500g water-)
i is Van't Hoff factor (1, assuming antifreeze is ethylene glycol -C₂H₄(OH)₂)
Replacing:
20°C = 1.86°C / m × moles solute / 0.5 kg solvent × 1
5.376 = moles solute
As molar mass of ethylene glycol is 62.07g/mol:
5.376 moles × (62.07g / 1mol) = <em>333.7g of antifreeze</em>.
Answer : Option C) Categoric.
Explanation : According to the question the researcher is studying the science of attractiveness and the test is conducted by the volunteers by showing the images of different people, so here we can judge that the study is gender based and has to include male or female. Hence, it can be called as categoric variable.
